Change search
Refine search result
59606162636465 3051 - 3100 of 3315
CiteExportLink to result list
Permanent link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Rows per page
  • 5
  • 10
  • 20
  • 50
  • 100
  • 250
Sort
  • Standard (Relevance)
  • Author A-Ö
  • Author Ö-A
  • Title A-Ö
  • Title Ö-A
  • Publication type A-Ö
  • Publication type Ö-A
  • Issued (Oldest first)
  • Issued (Newest first)
  • Created (Oldest first)
  • Created (Newest first)
  • Last updated (Oldest first)
  • Last updated (Newest first)
  • Disputation date (earliest first)
  • Disputation date (latest first)
  • Standard (Relevance)
  • Author A-Ö
  • Author Ö-A
  • Title A-Ö
  • Title Ö-A
  • Publication type A-Ö
  • Publication type Ö-A
  • Issued (Oldest first)
  • Issued (Newest first)
  • Created (Oldest first)
  • Created (Newest first)
  • Last updated (Oldest first)
  • Last updated (Newest first)
  • Disputation date (earliest first)
  • Disputation date (latest first)
Select
The maximal number of hits you can export is 250. When you want to export more records please use the 'Create feeds' function.
  • 3051. Yan, B.
    et al.
    Li, F.
    Wang, H.
    Sichen, Du
    KTH, School of Industrial Engineering and Management (ITM), Materials Science and Engineering.
    Study of Chromium Oxide Activities in EAF Slags2015In: Metallurgical and materials transactions. B, process metallurgy and materials processing science, ISSN 1073-5615, E-ISSN 1543-1916Article in journal (Refereed)
    Abstract [en]

    The activity coefficients of chromium in Cu-Cr melts were determined by equilibrating liquid copper with solid Cr<inf>2</inf>O<inf>3</inf> in CO-CO<inf>2</inf> atmosphere. The temperature dependence of the activity coefficients of chromium in Cu-Cr melts could be expressed as (Formula presented.) Based on the above results, the activities of bivalent and trivalent chromium oxide in some slags at 1873 K (1600 °C) were measured. The slags were equilibrated with Cu-Cr melts under two oxygen partial pressures ((Formula presented.) = 6.9 × 10−4 and 1.8 × 10−6 Pa, respectively). The morphology of the quenched slags and the solubility of chromium oxide in the melts were investigated by EPMA, SEM, and XRD. Under both oxygen partial pressures, the slags were saturated by the solid solution MgAl<inf>2−x</inf>Cr<inf>x</inf>O<inf>4−δ</inf>. At the low oxygen partial pressure (1.8 × 10−6 Pa), the content of Cr in the liquid phase varied from 0.4 to 1.6 mass pct with the total Cr content in the slags increasing from 1.3 to 10.8 mass pct. At the high oxygen partial pressure (6.9 × 10−4 Pa), the content of Cr in the liquid phase decreased to the level of 0.2 to 0.6 mass pct. Both the activities of CrO and Cr<inf>2</inf>O<inf>3</inf> in slag were found to increase approximately linearly with the increase of the total Cr content in slag. While the oxygen partial pressure had minor effect on the activity of Cr<inf>2</inf>O<inf>3</inf> in the slag, it had significant effect on the activity of CrO.

  • 3052. Yan, J. -Y
    et al.
    Zhang, W. -Z
    Borgenstam, Annika
    KTH, School of Industrial Engineering and Management (ITM), Materials Science and Engineering, Physical Metallurgy.
    Observations of surface relief of proeutectoid Widmanstätten cementite plates in a hypereutectoid carbon steel2013In: Metallurgical and Materials Transactions. A, ISSN 1073-5623, E-ISSN 1543-1940, Vol. 44, no 9, p. 4143-4149Article in journal (Refereed)
    Abstract [en]

    Proeutectoid Widmanstätten cementite in a hypereutectoid carbon steel was found to be associated with a surface relief effect. A hot-stage microscope was used for heat treatment and in situ observation. Widmanstätten cementite plates were obtained near the surface of the specimen. The surface relief effect of Widmanstätten cementite plates was quantitatively characterized by atomic force microscopy. It was found that the relief had either a typical tent shape or apex-lost tent shape. The relief tilt angles were of considerable dispersion, ranging from 20 deg to 50 deg.

  • 3053.
    Yang, Annika Fang
    KTH, School of Industrial Engineering and Management (ITM), Materials Science and Engineering.
    A pre-study of Hot Metal Desulphurization2012Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    In this thesis work, some basic concepts about desulphurizationof hot metal have been done based on a literature study. Two experimentaltrials have also been carried out to study the slags: one consider as areference and in the other trial, the amount of calcium carbide was reduced by150 kg. The average carbide efficiency has been improved from 21.3% in trial 1 to 26.0% in trail 2. Metaldroplets containing iron oxides are found in three of eight heats and most ofmetal droplets are surrounded by Ti-compounds. The slags mainly consisted of (Ca,O, Si) and (Ca, S), with some low content of other elements.

  • 3054.
    Yang, Annika Fang
    KTH, School of Industrial Engineering and Management (ITM), Materials Science and Engineering, Applied Process Metallurgy.
    Evaluation of Iron Losses during Desulfurazation of Hot Metal by Modern Reagents2015Licentiate thesis, comprehensive summary (Other academic)
  • 3055.
    Yang, Annika Fang
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Materials Science and Engineering.
    Karasev, Andrey
    KTH, School of Industrial Engineering and Management (ITM), Materials Science and Engineering, Applied Process Metallurgy.
    Jönsson, Pär Göran
    KTH, School of Industrial Engineering and Management (ITM), Materials Science and Engineering, Applied Process Metallurgy.
    Characterization of Metal Droplets in Slag after Desulfurization of Hot Metal2015In: ISIJ International, ISSN 0915-1559, E-ISSN 1347-5460, Vol. 55, no 3, p. 570-577Article in journal (Refereed)
    Abstract [en]

    Iron losses in slag during an intensive desulfurization of hot metal can reach 0.6-1.1% from the total amount of processed hot metal. The characteristics of different metal droplets (such as morphology, number, size, composition and solidification structure) in industrial slag samples after desulfurization were investigated using SEM. All metal droplets in the slag were classified into three groups according to morphology: Type A - spherical/oval; Type B - spherical/irregular; Type C - irregular. Thereafter, some mechanisms for involving of different metal droplets into the slag during desulfurization process were studied based on obtained characteristics of metal droplets. Moreover, a possibility to remove those metal droplets from the liquid slag was estimated based on Stokes law. In addition, the effect of some parameters (such as slag viscosity and size of different metal droplets in this slag) on the possibility to reduce the iron losses during desulfurization of hot metal was considered.

  • 3056.
    Yang, Annika Fang
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Materials Science and Engineering, Applied Process Metallurgy.
    Karasev, Andrey
    KTH, School of Industrial Engineering and Management (ITM), Materials Science and Engineering, Applied Process Metallurgy.
    Jönsson, Pär Göran
    KTH, School of Industrial Engineering and Management (ITM), Materials Science and Engineering, Applied Process Metallurgy.
    Effect of nepheline syenite on iron losses in slags during desulphurization of hot metalManuscript (preprint) (Other academic)
  • 3057.
    Yang, Jie
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Biomolecular and Organic Electronics. Linköping University, Faculty of Science & Engineering. University of Politecn Cataluna, Spain.
    Roa, J. J.
    University of Politecn Cataluna, Spain; University of Politecn Cataluna, Spain.
    Schwin, M.
    SECO Tools AB, Sweden.
    Odén, Magnus
    Linköping University, Department of Physics, Chemistry and Biology, Nanostructured Materials. Linköping University, Faculty of Science & Engineering.
    Johansson, Mats
    Linköping University, Department of Physics, Chemistry and Biology, Nanostructured Materials. Linköping University, Faculty of Science & Engineering. SECO Tools AB, Sweden.
    Llanes, L.
    University of Politecn Cataluna, Spain; University of Politecn Cataluna, Spain.
    Grinding-induced metallurgical alterations in the binder phase of WC-Co cemented carbides2017In: Materials Characterization, ISSN 1044-5803, E-ISSN 1873-4189, Vol. 134, p. 302-310Article in journal (Refereed)
    Abstract [en]

    The metallic binder phase dictates the toughening behavior of WC-Co cemented carbides (hardmetals), even though it occupies a relative small fraction of the composite. Studies on deformation and phase transformation of the binder constituent are scarce. Grinding represents a key manufacturing step in machining of hardmetal tools, and is well-recognized to induce surface integrity alterations. In this work, metallurgical alterations of the binder phase in ground WC-Co cemented carbides have been assessed by a combination of electron back scattered diffraction and transmission electron microscopy techniques. The Co-base binder experiences a martensitic phase transformation from fcc to hcp crystal structure, predominantly in the first 5 mu m below the surface. The hcp fraction decreases gradually along a depth of 10 mu m. Surface Co displays severe plastic deformation under the highest strain, resulting in formation of nanocrystalline grains in the first micrometer below the surface. Microstructural refinement within the binder phase is observed even at greater depth. Stacking faults were detected in most of the refined grains. The metallurgical alterations of the binder phase modify the local stress distribution during grinding, which affects the discerned subsurface microcracking. The resulting residual stress profile is the sum of multiple subsurface changes, such as phase transformation, severe plastic deformation and grain refinement, where it is discerned that the depth profile of the transformed hcp-Co fraction coincides with the grinding-induced residual stress profile.

  • 3058.
    Yang, Jie
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Biomolecular and Organic Electronics. Linköping University, Faculty of Science & Engineering. Univ Politecn Cataluna, Spain; AMES Sintered Met Components, Spain.
    Roa, J. J.
    Univ Politecn Cataluna, Spain; Univ Politecn Cataluna, Spain.
    Schwind, M.
    SECO Tools AB, Sweden.
    Odén, Magnus
    Linköping University, Department of Physics, Chemistry and Biology, Nanostructured Materials. Linköping University, Faculty of Science & Engineering.
    Johansson-Jöesaar, Mats
    Linköping University, Department of Physics, Chemistry and Biology, Nanostructured Materials. Linköping University, Faculty of Science & Engineering.
    Esteve, J.
    Univ Barcelona, Spain.
    Llanes, L.
    Univ Politecn Cataluna, Spain; Univ Politecn Cataluna, Spain.
    Implementation of advanced characterisation techniques for assessment of grinding effects on the surface integrity of WC-Co cemented carbides2018In: Powder Metallurgy, ISSN 0032-5899, E-ISSN 1743-2901, Vol. 61, no 2, p. 100-105Article in journal (Refereed)
    Abstract [en]

    Grinding is a key step on the manufacturing process of WC-Co cemented carbides (hardmetals). In this work, an investigation of grinding effects on the surface integrity of hardmetals is conducted. It is done by combining diverse advanced characterisation techniques: X-ray diffraction, field emission-scanning electron microscopy, electron back scatter diffraction, focused ion beam - 3D tomography and transmission electron microscopy. The study is carried out in a fine-grained WC-Co grade. Besides ground state, polished surface finish condition is assessed for comparison purposes. It is evidenced that grinding induces significant alterations: 3D tomography illustrates microcracking exists down to 2.5 mu m depth with a highly anisotropic distribution at the subsurface, large compressive residual stresses extending until subsurface levels of about 12 mu m, and phase transformation of binder from the original fcc phase into the hcp one, as well as severe plastic deformation observed within the binder at the surface level.

  • 3059.
    Yang, Qixing
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
    Erosion of refractory by gas injection1990Licentiate thesis, comprehensive summary (Other academic)
  • 3060.
    Yang, Qixing
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
    The mechanical wear of tuyere refractory and stirring plugs in BOF steelmaking1996Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Water modelling investigations of pressure change at tuyere tip or back attack and wear of H3B03 disks, as well as high temperature modelling wear tests of BOF refractory using single- or double-tuyere and Ar or N2 gas, have been carried out to study mechanisms for mechanical wear of the refractory for BOF stirring tuyeres and plugs. A new nominal Mach number, M*', was defined and adopted as the criterion for correlating test data. Both the back attack frequency and the Wr, wear rate of H3B03 disks, increase with M*' at M*'<1, reach the maximum near M*'=1 and start to decrease after M*'>1. The wear rate, Wr, of MgO-C bricks tested using steel at 1550°C depends strongly on tuyere characters and increases with M*' until M*'=l, similar to the trends for the back attack and disk Wr. Another brick wear parameter, the radius of deep wear area, RDA, displays a behaviour similar to that of the Wr. The estimated refractory wear rate, Wr*, at M*'<_1 can be related to mM*', the defined nominal momentum rate from tuyere gas injection. The RDA measured from single-tuyere tests can be used to estimate influences of tuyere interaction on the refractory wear rate. When the DTC, the distance between tuyeres for a double-tuyere test, is less than twice the RDA, values of Wr are increased. The refractory wear rate will no be influenced with DTC>2RDA. Tuyere gas flowrate can also be reduced to diminish the interaction. Equations are derived, based on proposed bubble expansion wear mechanism, to compute values of estimated RDA, as well as RSA (Radius of Shear wear Area), at M*'<_1 which can be used to eliminate detrimental effects of tuyere interaction and for the plug design. The M*' values for tuyeres should be either less than 0.5 or greater than 1.5 and values of mM*' should be low to reduce the refractory wear for the stirring tuyeres and plugs in BOF steelmaking. A smaller tuyere inner diameter sets the maximum wear parameters to a lower level and can be chosen to decrease the wear, without decreasing the gas flowrate.

  • 3061.
    Yang, Qixing
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
    Björkman, Bo
    Effects of bubble expansion on wear of refractory for BOF stirring plugs embedding tuyeres1997In: Steel Research International, ISSN 1611-3683, E-ISSN 1869-344X, Vol. 68, no 3, p. 107-114Article in journal (Refereed)
    Abstract [en]

    Single tuyere wear tests of MgO-C and burnt magnesia bricks were performed to study relations between tuyere characteristics and refractory wear parameters, with emphasis on the wear zone geometry. Either Ar or N2 was used as injected gas and the test temperature for liquid metal was 1400, 1550 and 1700 °C. A bubble expansion wear mechanism was proposed for the mechanical wear of tuyere refractory by comparison of bubble radii and the wear zone geometry of refractory bricks and H3BO3 disks. Equations are derived to predict the deep and shear wear zone radii and the refractory wear rate at values of the nominal Mach number up to one. These equations can be used for an optimum design of single- and multiple-tuyere plugs for combined blowing BOF, as well as for optimization of gas stirring operation to reduce the wear of MgO-C refractory around the tuyere and for the plugs.

  • 3062. Yang, Qixing
    et al.
    Björkman, Bo
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
    The wear of converter stirring plugs and the tuyere gas injection: a study by high temperature modelling1995In: Scaninject VII: 7th International Conference on Refining Processes, Luleå, Sweden, June 7-8, 1995, MEFOS , 1995, Vol. II, p. 257-282Conference paper (Refereed)
    Abstract [en]

    To obtain more information on wear mechanisms of stirring plugs for oxygen converters, the present authors carried out wear tests of MgO-C bricks at 1550 deg C for approx6 h. Tubular tuyeres were used to inject argon gas into liquid metal contained in crucibles. The wear examinations show that mechanical stresses aided by thermal and chemcial stresses are mainly responsible for the brick wear which result in two wear patterns on brick surfaces: the deep wear or back-attack wear and the shear wear. A new criterion, M exp *' , is defined by the ratio of the injected gas mass flowrate, m, to the critical flowrate, m exp * . The M exp *' better characterises the properties of gas-liuqid systems and relates the high wear of the bricks directly to condition changes for gas injection at/near tuyere outlet. The brick wear rates, W sub r , were shown to increase with M exp *' up to a M exp *' value near to one and become constant or decreasing as the M exp *' -values are further increased. Based on results from the present study, tuyeres with i.d. < =2 mm should be operated with M exp *' -values ranging from 0.15-0.45 in order to reduce the wear of plug refractory and to achieve optimum plug operations

  • 3063.
    Yang, Qixing
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
    Björkman, Bo
    The wear of converter stirring plugs and the tuyere gas injection: a study by high-temperature modelling1995In: Scandinavian journal of metallurgy, ISSN 0371-0459, E-ISSN 1600-0692, Vol. 24, no 5-6, p. 242-254Article in journal (Refereed)
    Abstract [en]

    To obtain more information on wear mechanisms of stirring plugs for oxygen converters, the present authors carried out wear tests of MgO-C bricks at 1550°C for about 6 h. Tubular tuyeres were used to inject Ar gas into liquid metal contained in crucibles. The wear examinations show that mechanical stresses aided by thermal and chemical stresses are mainly responsible for the brick wear which result in two wear patterns on brick surfaces: the deep wear or back-attack wear and the shear wear. A new criterion, M* prime , is defined by the ratio of the injected gas mass flowrate, m, to the critical flowrate, m*. The M* prime better characterises the properties of gas-liquid systems and relates the high wear of the bricks directly to condition changes for gas injection at/near tuyere outlet. The brick wear rates, Wr, were shown to increase with M* prime up to a M* prime value near to unity, and become constant or decreasing as the M* prime -values are further increased. Based on results from the present study, tuyeres with i.d. <=2 mm should be operated with M* prime -values ranging from 0.15 to 0.45 in order to reduce the wear of plug refractory and to achieve optimum plug operations

  • 3064. Yang, Qixing
    et al.
    Björkman, Bo
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
    Carlsson, Göran
    Wear of MgO-C refractory for the BOF stirring plug with multiple tuyeres and the tuyere interaction1996In: 79th Steelmaking Conference proceedings: Pittsburgh meeting, March 24 - 27, 1996, Pittsburgh, Pa: Iron and Steel Society , 1996, p. 439-450Conference paper (Refereed)
    Abstract [en]

    Wearing effects of tuyere interaction on MgO-C refractory for the BOF stirring plug with multiple tuyeres have been studied by performing single-tuyere and double-tuyere wear tests using molten steel of 1550 °C and Ar gas. Two tuyeres were set in the refractory with different distance between their centres for the double-tuyere wear tests to simulate service conditions for the multiple-tuyere plugs. The results show that the wear is severe with a tuyere distance of 12 mm and 10 Nl/min Ar flowrate for each tuyere due to an overlap of the high wear zone around the tuyeres. The wear is reduced to the level of wear for the single tuyere when the tuyere distance is increased to 24 mm or more. With a tuyere distance less than 50 mm, an overlap of the shear zone for the tuyeres occurs giving an elliptic shear wear zone around tuyeres. With a distance of 50 mm for the tuyeres, the interaction effects on the refractory wear disappear. Based on test results and the bubble expansion wear mechanism, methods for estimating, reducing and eliminating mechanical wearing effects of tuyere interaction are discussed and suggested

  • 3065. Yang, Qixing
    et al.
    Engström, Fredrik
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
    Björkman, Bo
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
    Adolfsson, Daniel
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
    Modification study of a steel slag to prevent the slag disintegration after metal recovery and to enhance slag utilization2009In: Molten 2009: proceedings of the VIII International Conference on Molten Slags, Fluxes & Salts, 18-21 January 2009, Santiago, Chile / [ed] Mario Sanchez; Roberto Parra; Gabriel Riveros; Carlos Diaz, Concepción, Chile: GECAMIN, 2009, p. 33-41Conference paper (Refereed)
    Abstract [en]

    A slag sample was produced during laboratory reduction tests of a steel slag for metal recovery. The reduction of the metal oxides changed slag basicity (CaO/SiO2) to about 1.6 and led to the formation of g-phase of dicalcium silicate, g-Ca2SiO4, which resulted in disintegration of the slag sample. A modification study of the slag sample after reduction was performed. The study aimed at acquiring data and fundamental information for choosing environmentally friendly and cost effective methods for preventing slag disintegration in order to increase slag utilization. Effects of some additives, containing SiO2 or P2O5, on the formation of the g-Ca2SiO4 were examined via slag melting tests. The slag was also modified by fast cooling, via air granulation using a laboratory granulation system. In these modification tests, a laboratory induction furnace was used to melt the samples at approximately 1700°C. Samples obtained before and after the modification tests were characterized. The study results showed that g-Ca2SiO4 and fines did not appear by adding MCP-F or a product from iron ore processing to increase P2O5 content in the reduced slag from a very low level, 0.07%, to around 0.3% or higher. A sand addition of 5.12% in the reduced slag could decrease slag CaO/SiO2 value to 1.34, which prevented Ca2SiO4 formation and slag disintegration. The reduced slag was cooled quickly via air granulation, which prevented formations of g-Ca2SiO4 in slag granules. Based on results from the melting tests and other literature, fundamental aspects regarding slag modification and treatment are discussed, along with utilization of the slag after the oxide reduction and modification.

  • 3066.
    Yang, Qixing
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
    Engström, Fredrik
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
    Björkman, Bo
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
    Li, Jianli
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
    Xu, Anjun
    USTB Beijing.
    Dissolution behavior of fluorine in AOD slag from the production of stainless steel after treatment for volume stabilization2012In: Scanmet IV: 4th International Conference on Process Development in Iron and Steelmaking, Luleå: MEFOS , 2012, Vol. 2, p. 517-526Conference paper (Refereed)
    Abstract [en]

    The slag tapped from AOD (Argon Oxygen Decarburization) converter disintegrates, sometimes, during cooling. Slag fines from the disintegration are difficult to handle and to use as materials for construction purposes. In our early research work, AOD slag samples were modified by agents containing B or P elements. Different slag cooling procedures were also used, including cooling inside crucibles after re-melting and granulation by water and gas. By the modification, the slag samples gained the volume stability and mechanical properties required for its utilization as construction materials.Different types of stainless steel slag from Outokumpu Stainless Company have been used to manufacture environmentally sound and ce-marked construction products. Fluorine leaching from some of the AOD slag samples were investigated. In some other steelmaking processes, such as hot metal pretreatment, secondary steel refining and the production of high alloyed steels, fluorite can be charged as a slag forming agent, with some F and CaF2 existing in the slag. When these slags are reused as road construction or landfill materials, a potential fluorine contamination to the ground water may occur.The present research work is carried out regarding both the volume stability and F-immobilization for AOD slag samples. The studied slag samples consist of new ones from plant gas granulation tests and some old ones from our early studies. Compositions and cooling conditions are selected as main parameters for slag tests using laboratory equipment. Samples from the plant and laboratory slag tests are characterized by XRD, SEM and leaching with EN12457-2/3. Formations of mineral phases for F-immobilization in the slag samples are also predict using FACTSAGE program.Results from the present study indicate that the chemical composition and cooling condition for a slag are the two important parameters to control F leaching. These two parameters should be considered together in an optimum way to treat the slag for fluorine immobilization.It may be possible, based on the results obtained, to develop some environmental friendly and cost effective methods for the stainless steel industry to treat the AOD slag. Some slag products with high volume stability and minimum F-dissolution may thus be obtained to use as construction materials for saving valuable natural resources.

  • 3067.
    Yang, Qixing
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
    Engström, Fredrik
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
    Haase, Björn
    Wedholm, Anita
    Stabilization of EAF slag for use as construction material2008In: REWAS 2008: Global Symposium on Recycling, Waste Treatment / [ed] B. Mishra; C. Ludwig; C. Das, Minerals, Metals & Materials Society, 2008, p. 49-54Conference paper (Refereed)
    Abstract [en]

    MiMeR, the Minerals and Metals Recycling Research Centre at Lulea University of Technology, Sweden, started industry-related research work to stabilize an EAF slag from Hoganas AB with of CaO/SiO2 values near to 3.2. The intention was to determine the suitability of the EAF slag as construction material after stabilization. Some of the stabilizers effective for preventing disintegration of AOD slag were examined in laboratory tests for stabilization of the EAF slag. The EAF slag samples were mixed together with stabilizers for melting at 1600{o}C and then cooling in a crucible system. With a laboratory granulation system, the liquid EAF slag was cooled rapidly using air. Samples from the tests were characterized by different techniques, including XRD and SEM. Some of the results from the work may be useful for preventing slag disintegration and, thus, enhancing utilization of the EAF slag as construction material, thereby saving valuable natural resources

  • 3068.
    Yang, Qixing
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
    Engström, Fredrik
    Tossavainen, Mia
    Adolfsson, Daniel
    Treatments of AOD Slag to enhance recycling and resource conservation2005In: Securing the future: international conference on mining and the environment, metals and energy recovery : proceedings, Stockholm: SweMin , 2005Conference paper (Refereed)
    Abstract [en]

    Laboratory treatment tests of AOD slag from stainless steelmaking have been performed by MiMeR. An induction furnace was used for slag reduction tests. The reduced slag was either water granulated or cooled in an Al2O3 crucible. Metal droplets, suitable for recycling as metallic materials in the steelmaking, were recovered after the slag granulation. Characterizations of slag samples from the tests show considerable influences of the treatments on physical and mineralogical properties of the slag. Some other possible methods for treatments and utilization of the slag were also discussed.

  • 3069.
    Yang, Qixing
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
    Engström, Fredrik
    Tossavainen, Mia
    He, Mingzhao
    Wang, Zheng
    Luleå tekniska universitet.
    AOD slag treatments to recover metal and to prevent slag dusting2005In: 7th Nordic-Japan Symposium on Science and Technology of Process Metallurgy, 2005, p. 14-Conference paper (Refereed)
  • 3070.
    Yang, Qixing
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
    Gustafsson, Börge
    Uddeholm Tooling AB.
    Upgrading of EAF dust by smelting in the electric arc furnace at Uddeholm Tooling AB2002In: TMS Fall 2002 Extraction and Processing Division Meeting on Recycling and Waste Treatment in Mineral and Metal Processing: Technical and Economic Aspects / [ed] Bo Björkman; Caisa Samuelsson; Jan-Olov Wikström, Luleå: MEFOS , 2002, Vol. 2, p. 231-240Conference paper (Refereed)
  • 3071.
    Yang, Qixing
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
    Gustafsson, Börje
    Uddeholm Tooling, Hagfors.
    Studies on dust recycling in the electric arc furnace at Uddeholm Tooling AB2003In: Scandinavian journal of metallurgy, ISSN 0371-0459, E-ISSN 1600-0692, Vol. 32, no 3, p. 147-156Article in journal (Refereed)
    Abstract [en]

    The electric arc furnace (EAF) generates dust containing about 21% Zn during primary steelmaking at Uddeholm Tooling AB. Research work on upgrading of the dust has been carried out jointly by Uddeholm Tooling AB and MiMeR, Minerals and Metals Recycling Research Centre, at Luleå University of Technology. The work included laboratory studies and plant trials. The laboratory studies, with 6 dust smelting tests at temperatures around 1650°C, demonstrated that the smelting had no negative effects on qualities of the steel and slag. It was also shown that both carbon and silicon could be used to reduce the oxides in the dust, leading to high metal recoveries. Based on the study results, plant trials were performed at Uddeholm Tooling AB. The trials consisted of 100 EAF heats, recycling dust at a rate of 925 kg/heat. No negative impact has been found on the furnace products and production. The Zn content of the obtained dust increased by 11% and the weight of the generated dust decreased by 42%. The material costs for the dust recycling during the trials were rather low, $0.4 (4-5 SEK)/tonne steel. Some of the test results are interpreted by virtue of mass and energy balances of the dust smelting calculated using the computer software "Chemsage." By utilizing results from the tests and calculations, the energy consumption for dust smelting was estimated.

  • 3072.
    Yang, Qixing
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
    Gustavsson, Håkan
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Fluid and Experimental Mechanics.
    Effects of gas jet instability on refractory wear: a study by high-speed photography1992In: Scandinavian journal of metallurgy, ISSN 0371-0459, E-ISSN 1600-0692, Vol. 21, no 1, p. 15-26Article in journal (Refereed)
    Abstract [en]

    To study influences of gas jet instability on tuyere refractory wear, gas injection was performed in an air-water system with a tuyere of 2 mm inner diameter. High-speed photography was used, with a framing rate of 8000 pictures per second, to film the tip region of a free and a half free tuyere. Characteristics of the cavity formed as a result of the jet instability were measured from the films, and the results were used in equations of bubble dynamics to calculate the pressure generated by the cavity motion. The film sequences show that as a result of the distortion of the gas-liquid interface, a throat in the gas jet is formed about 1.5D (tuyere i.d.) downstream of the tuyere tip. Radially moving gas starts to form an expanding cavity. The radius of the throat increases as it is pushed forward by the cavity expansion. With its radius reaching the maximum, the cavity stops growing. When the cavity collapses, bubble swarms are generated in the region near the tuyere. The cavity expands to 2D-4D (tuyere i.d.) within 1-15 ms. The maximum velocity of the expansion is about 10 m/s and acceleration ranges from 20 to 80 m/s2. The pressure calculated by using the cavity expansion data is in good agreement with the pressure measured at back-attack, which is around one half of the absolute pressure for the gas injection. This implies that the back-attack and cavity expansion are the same phenomenon. Passing the transition point of flow regimes the pressure increases very slowly as the injection rate increases. Occassionally, the cavity does not collapse immediately and it contracts after reaching the maximum radius. The cavity contraction generally takes longer than the expansion, with a velocity of about 2 m/s. The pressure reduction from the contraction is less than 0.1 bar which can not cause the formation of vapour bubbles in the liquid. By the cavity expansion, a liquid flow is set up which deforms and disintegrates gas bubbles nearby. At the moment of disintegration, liquid penetrates the concave side of the deformed bubble. The liquid flow may lead to an impact pressure of 30-90 bar in water and 210-630 bar in liquid steel. This pressure may cause refractory erosion with a pattern similar to that previously observed on H3BO3 disk surface. Besides the pitting erosion of the tuyere refractory, the influences of the jet instability on other factors of the refractory wear are also discussed.

  • 3073.
    Yang, Qixing
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
    Gustavsson, Håkan
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Fluid and Experimental Mechanics.
    Erosion of refractory during gas injection: a cavitation based model1990In: Scandinavian journal of metallurgy, ISSN 0371-0459, E-ISSN 1600-0692, Vol. 19, no 3, p. 127-137Article in journal (Refereed)
    Abstract [en]

    The problem of tuyere refractory wear has been studied in an air-water model using a 4 mm diameter tuyere. Erosion tests, with boric acid (H(3)BO(3)) disks as refractory simulators, and measurements of back-attack frequency were carried out. The erosion pattern showed two distinct features; isolated elliptical pits and a continuous irregular shear wear pattern. The influence of the surface hardness and gas flow rate on these features was investigated. Pitting was found most frequently on disks formed at the lowest pressure (10 tons), but for pressures greater than 20 tons little difference was seen between disks. When the gas flow was in the bubbling regime, pitting was observed inside the region closest to the tuyere tip, with a maximum at the transition to jetting flow. Occasionally, pits could still be observed when the gas flow rate was rather high (NMa=1.82). The irregular wear pattern appeared independent of disk surface properties, however, sensitive to the gas flow rate. In the bubble flow regime, the wear was seen only outside a certain radius, which corresponds well to the radius of the bubbles. In the jetting regime, the wear was also observed close to the tuyere. The disk weight loss showed a maximum in the bubbling-to-jetting transition region, where the back-attack frequency also reached a maximum. The results support the idea that cavitation erosion, through liquid microjet pitting, is the main mechanical wear agent. A model for the generation and

  • 3074.
    Yang, Qixing
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
    Gustavsson, Håkan
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Fluid and Experimental Mechanics.
    Buström, Eric
    Swerea MEFOS AB.
    Erosion of referactory during gas injection: a cavitation based model1989In: Scaninject V: 5th international conference on ladle metallurgy, Luleå, Sweden, June 6-8, 1989, MEFOS , 1989, Vol. I, p. 259-289Conference paper (Refereed)
    Abstract [en]

    The problem of tuyere refractory wear has been studied in an air--water model using a 4 mm diamter tuyere. Erosion tests, with boric acid (H sub 3 BO sub 3 ) disks as refactory simulators, and measurements of back-attack frequency were carried out. The erosion pattern shows two distinct features: isolated elliptical pits and a continuous irregular shear wear pattern. The influence on these features of the surface hardness and gas flow rate was investigated. 24 ref.--

  • 3075.
    Yang, Qixing
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Minerals and Metallurgical Engineering.
    Haase, Björn
    Engström, Fredrik
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Minerals and Metallurgical Engineering.
    Björkman, Bo
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Minerals and Metallurgical Engineering.
    Stabilization studies of EAF slag for its use as materials in construction2012In: Proceedings, Asiasteel 2012, The Chinese Society for Metals , 2012Conference paper (Refereed)
    Abstract [en]

    At Halmstadsverken, the steel plant of Höganäs AB in Sweden, steel grades with low carbon contents were produced using an Electric Arc Furnaces (EAF). Very often, the tapped EAF slag disintegrated during cooling. Slag fines from the disintegration are difficult to handle and to use as materials for construction purposes. MiMeR, Minerals and Metals Recycling Research Centre at Luleå University of Technology (LTU), has, in a close cooperation with Höganäs AB, performed test work to treat the EAF slag. The study has been performed within the research program “Towards a Closed Steel Ecocycle”, carried out by Jernkontoret, with financial support from the Foundation for Environment Strategic Research in Sweden. Some of the projects in the program are aimed at enhancing utilizations of steelmaking slags as building materials. In the first study stage, the EAF slag samples, mixed together with stabilizers, were melted at 1610ºC and then cooled in a crucible system. The liquid EAF slag was also cooled rapidly by air using a laboratory granulation system. In the second study stage, by referring to the early results, two test campaigns were carried out at Halmstadsverken to stabilize EAF slag using a stabilizing additive, high in P2O5. The slag after the stabilization was cooled in air and by water, providing slag samples of large quantities for later long-term aging and stability tests. Test operations were performed without disturbing the normal EAF steel production. In this paper, some of the details of test operations are described and results obtained from the two study stages are presented and discussed.

  • 3076.
    Yang, Qixing
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
    Haase, Björn
    Höganäs Sweden AB, SE-263 83 Höganäs.
    Han, Fenglan
    School of Material Science & Engineering, Beifang University of Nationality, Yinchuan, Ningxia.
    Engström, Fredrik
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
    Li, Jianli
    Department of Ferrous Metallurgy, School of Metallurgical and Ecological Engineering, University of Science and Technology Beijing.
    Xu, Anjun
    Department of Ferrous Metallurgy, School of Metallurgical and Ecological Engineering, University of Science and Technology Beijing.
    Björkman, Bo
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
    Laboratory treatments of EAF slag for its use in construction2013In: Advanced Materials Research, ISSN 1022-6680, E-ISSN 1662-8985, Vol. 726-731, p. 2921-2930Article in journal (Refereed)
    Abstract [en]

    Laboratory treatments of a plant EAF slag sample 71686 were conducted using stabilizers containing P2O5 and air granulation. The results show that it is necessary to add the stabilizers to increase contents of P2O5 from 0.39% to 0.7% for the slag stabilization. By a fast air cooling, most of the granules from the granulation are spherical, with a low internal porosity and dense structure. Content of Fe2O3 in the granules increased from 7.92% to 18.4% and FeO decreased from 14.3% to 7.8%, due to an oxidation during the slag granulation. Contents of metal elements, As, Cd, Cr, Mo, Pb, Ni and Zn, in the leachates from the treated slag samples were lower than the limit values for leaching from inert wastes pursuant to Directive 1999/31/EC. The slag samples after the treatments may then be regarded as environmentally friendly to use in construction

  • 3077.
    Yang, Qixing
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
    Haase, Björn
    Höganäs Sweden AB, SE-263 83 Höganäs.
    Han, Fenglan
    School of Material Science & Engineering, Beifang University of Nationality, Yinchuan, Ningxia.
    Xu, Anjun
    Department of Ferrous Metallurgy, School of Metallurgical and Ecological Engineering, University of Science and Technology Beijing.
    Engström, Fredrik
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
    Li, Jianli
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
    Björkman, Bo
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
    Plant treatments of EAF slag for its use as construction materials2013In: Advanced Materials Research, ISSN 1022-6680, E-ISSN 1662-8985, Vol. 750-752, p. 1244-1253Article in journal (Refereed)
  • 3078. Yang, Qixing
    et al.
    Holmberg, N
    Menad, Nourreddine
    Björkman, Bo
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
    A fundamental study on recycling of wastes from stainless steel plants via the electric arc furnace2000In: 58th Electric Furnace Conference and 17th Process Technology Conference, Iron and Steel Society , 2000, p. 195-207Conference paper (Refereed)
    Abstract [en]

    Waste briquettes of high carbon contents have been smelted using an induction furnace in tests to gain fundamental information for EAF operations of the briquette smelting. The briquettes amounted to 5-15% of the weights of the metal charges, stainless steel scrap and alloys.

  • 3079. Yang, Qixing
    et al.
    Holmberg, Nils
    Outokumpu.
    Björkman, Bo
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
    EAF smelting trials of briquettes at Avesta works of Outokumpu Stainless Steel AB for recycling oily mill scale sludge from stainless steel production2008In: SCANMET III: 3rd International Conference on Process Development in Iron and Steelmaking, 8-11 June 2008, Luleå, Sweden, Luleå: MEFOS , 2008, Vol. 1, p. 561-570Conference paper (Refereed)
    Abstract [en]

    The production EAF of Avesta Works, Outokumpu Stainless AB, has been used to perform smelting reduction trials of briquettes consisting of oily mill scale sludge, carbon and other wastes. The trials were among several important activities in studies on waste recycling by EAF smelting carried out jointly by Avesta Works and MiMeR, the Minerals and Metals Recycling Research Centre, at Luleå University of Technology. A total of 7 briquette smelting trials were performed. The heats were processed smoothly smelting 3 tonnes of briquettes or 3,4% of the weight for metal charges. Quantities of FeSi powder and O2 gas injected and electric energy supplied were increased while the briquette weight was increased to 6 tonnes. No impacts were found on analyses of the crude stainless steel tapped from the EAF during the trials. Results of the briquette smelting have been evaluated by referring to the data from the reference heats and results from early laboratory tests. The recovery of Cr, Ni and Fe elements from the briquettes was nearly complete and was found to occur mainly through carbon reduction. Positive effects of briquette smelting on protecting metallic charges against gaseous oxidation have also been identified. This protection was through CO gas, generated from solid state C-O reaction in the briquettes, reacting with oxygen in the intruding air. The protection reduced losses of Cr, Ni and Fe elements from metallic charges to the slag. The slag weights were not increased in three trials as compared with the reference heats. There were moderate increases in the slag weights in four trial heats. The increases were, nevertheless, lower by 52-69% than the slag weights generated by a Si-reduction of the briquette oxides. By smelting 6-tonnes of briquettes in the trials, reliable information and results on C-O reactions in the briquettes for recovery of metal elements in the production EAF were obtained. After the trials, carbon-waste briquettes amounting to 1-3 tonnes were smelted very smoothly in many of the EAF heats at Avesta Works to recycle the oily mill scale sludge and other wastes from stainless steel production. The metal recoveries from the briquettes were then estimated based on the information and results of the C-O reaction and metal recovery obtained from the present trial heats.

  • 3080. Yang, Qixing
    et al.
    Holmberg, Nils
    Outokumpu Stainless AB, Avesta Works.
    Björkman, Bo
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
    EAF smelting trials of waste-carbon briquettes at Avesta works of Outokumpu Stainless AB for recycling oily mill scale sludge from stainless steel production2009In: Steel Research International, ISSN 1611-3683, E-ISSN 1869-344X, Vol. 80, no 6, p. 422-428Article in journal (Refereed)
    Abstract [en]

    The EAF steel plant of Avesta Works, Outokumpu Stainless AB, has been used to perform smelting reduction trials of briquettes consisting of oily mill scale sludge, carbon and other wastes. A total of 7 briquette smelting trials were performed. The heats were processed smoothly smelting 3 t of briquettes or 3.4 mass-% of metal charges. The quantities of FeSi powder and 02 gas injected and electric energy supplied were increased to smelt briquettes of 6 t. No impacts were found on the analyses of the crude stainless steel tapped from the EAF during the trials. The results of the briquette smelting have been evaluated by referring to the data from the reference heats and results from earlier laboratory tests. The recovery of Cr, Ni and Fe elements from the briquettes was nearly complete and was found to occur mainly through carbon reduction. The slag masses were not increased in three trials as compared with the reference heats. There were moderate increases in the slag masses in four trial heats. The increases were, nevertheless, lower by 52-69% than the slag masses generated by Si-reduction of the briquette oxides. Afterwards, by referring results from the present trials, waste-carbon briquettes amounting to 1-3 t were smelted very smoothly in many of the EAF heats at Avesta Works to recycle the oily mill scale sludge and other wastes from stainless steel production.

  • 3081. Yang, Qixing
    et al.
    Holmberg, Nils
    Menad, Nourreddine
    Björkman, Bo
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
    A laboratory study on smelt-reduction of briquettes made of wastes from stainless steel production1999In: REWAS '99: Global Symposium on Recycling, Waste Treatment and Clean Technology : proceedings of the "REWAS'99: Global Symposium on Recycling, Waste Treatment and Clean Technology", held in San Sebastián, Spain, September 5 - 9, 1999 : TMS Fall 1999 Extraction and Process Metallurgy Meeting / [ed] I. Gaballah, 1999, p. 1061-1072Conference paper (Refereed)
    Abstract [en]

    Wastes from stainless steel production were briquetted together with carbon for smelt-reduction in the electric arc furnace, EAF, to achieve an internal recycling. A laboratory induction furnace was used to simulate the EAF to study the disintegration of the briquettes under heating and recovery of metals from briquettes melted together with stainless steel and slag-former. The influences of test conditions on carbon reduction of oxides in the briquettes were also examined. The briquettes endured heating at 1186°C under load and could be charged to the melt in small quantity without causing serious splashing. For a high metal recovery, it was necessary to charge the briquettes together with slag-former. Small local zones of smelt-reduction with high carbon concentration could thus be formed during heating. Silicon content in the metal near to the briquettes should be minimised to achieve a high degree of carbon reduction. Based on results obtained from this study, suggestions were made on smooth operations of smelt-reduction of the briquettes by using electric arc furnaces of large scale

  • 3082.
    Yang, Qixing
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
    Menad, Nourreddine
    Smelting of EAF and BF dust in combination with scrap melting to recycle the by-products from steel industry2005In: Proceedings of the REWAS '04: Global Symposium on Recycling, Waste Treatment and Clean Technology held in Madrid, Spain, September 26 - 29, 2004, Minerals, Metals & Materials Society, 2005, p. 2729-2738Conference paper (Refereed)
    Abstract [en]

    The baghouse dust generated from the electric arc furnace (EAF) process must be treated using environmentally and economically sound methods. One treatment step is to smelt the dust in the EAF so the dust can be upgraded for further processing. Parameters related to optimum dust smelting in the EAF were studied in the present laboratory tests. An induction furnace was used to smelt test charges, steel parts weighing 5 kg, slag formers and the EAF dust pellets (EAFDP) with a steel weight of 2%. Eight tests were performed. Reducing agents for Zn oxides in the EAFDP were coke, blast furnace dust, solid iron and liquid iron with temperature of 1650°C. Influences of contacts between the EAFDP and reducing agents on Zn dissolution in liquid steel were examined in some detail. It was demonstrated by the tests that material mixing and heating were important for minimizing the impact of the EAFDP smelting on steel and slag properties when using either coke or blast furnace dust as reducing agents. Based on results from the present laboratory tests, some suggestions were made for production-scale recycling of EAFDP in the EAF

  • 3083. Yang, Qixing
    et al.
    Nedar, Lotta
    Outokumpu, Avesta.
    Engström, Fredrik
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
    He, Mingzhao
    Treatments of AOD slag to produce aggregates for road construction2006In: AISTech 2006: Proceedings of the Iron & Steel Technology Conference and Exposition, Warrendale, Pa.: Iron and Steel Society , 2006, Vol. 1, p. 573-583Conference paper (Refereed)
  • 3084.
    Yang, Qixing
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Minerals and Metallurgical Engineering.
    Xu, Anjun
    State Key Laboratory of Advanced Metallurgy, University of Science and Technology Beijing.
    Engström, Fredrik
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Minerals and Metallurgical Engineering.
    Han, Fenglan
    School of Material Science and Engineering, Beifang University of Nationalities, Yinchuan.
    Xue, Peng
    School of Metallurgical and Ecological Engineering, University of Science and Technology, Beijing.
    He, Dongfeng
    School of Metallurgical and Ecological Engineering, University of Science and Technology, Beijing.
    Björkman, Bo
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Minerals and Metallurgical Engineering.
    Dissolution behavior of fluorine from AOD slag after treatments for volume stabilization2014In: Applied Mechanics and Materials, ISSN 1660-9336, E-ISSN 1662-7482, Vol. 587-589, p. 849-855Article in journal (Refereed)
    Abstract [en]

    AOD slag samples from steel works of Outokumpu Stainless Company were used to study F-dissolution relating to treatments for volume stabilization. Results from the slag tests and sample characterizations indicate that the slag re-melting with or without reduction and granulation with either water or gas have rather small effects on F leaching, as well as formation of different C2S polymorphs. The chemical composition and cooling condition are the two important parameters to control F leaching from slag samples. These two parameters should be combined together in an optimum way by the steel industry to treat slags for F-immobilization.

  • 3085.
    Yang, Qixing
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Minerals and Metallurgical Engineering.
    Xu, An-Jun
    State Key Laboratory of Advanced Metallurgy, University of Science and Technology Beijing, School of Metallurgical and Ecological Engineering, University of Science and Technology, Beijing.
    Xue, Peng
    School of Metallurgical and Ecological Engineering, University of Science and Technology, Beijing , Department of Ferrous Metallurgy, School of Metallurgical and Ecological Engineering, University of Science and Technology Beijing.
    He, Dog-feng
    Department of Ferrous Metallurgy, School of Metallurgical and Ecological Engineering, University of Science and Technology Beijing.
    Li, Jian-Li
    State Key Laboratory of Advanced Metallurgy, University of Science and Technology Beijing, Key Laboratory for Ferrous Metallurgy and Resources Utilization of Ministry of Education, Wuhan University of Science and Technology, Wuhan , Department of Ferrous Metallurgy, School of Metallurgical and Ecological Engineering, University of Science and Technology Beijing.
    Björkman, Bo
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Minerals and Metallurgical Engineering.
    Briquette Smelting in Electric Arc Furnace to Recycle Wastes from Stainless Steel Production2015In: Journal of Iron and Steel Research International, ISSN 1006-706X, E-ISSN 2210-3988, Vol. 22, no Suppl. 1, p. 10-16Article in journal (Refereed)
    Abstract [en]

    Wastes from stainless steel production were briquetted together with carbon for smelt-reduction in the electric arc furnace, EAF, to achieve an internal recycling. A laboratory induction furnace was used to simulate the EAF. With a close simulation of the smelting, disintegration of the briquettes heated under load and recovery of metals from briquettes melted together with stainless steel and slag former were investigated. The influences of test conditions on carbon reduction of oxides in the briquettes were also examined. The briquettes endured heating at 1 186 °C under load of 3.5 kg and could be charged to the melt in small quantity without causing serious splashing. For a high metal recovery, it was necessary to charge the briquettes together with slag former. Small local zones of smelt-reduction with high carbon concentration could thus be formed during the charger heating. Silicon content in the metal near to the briquettes should be minimised to achieve a high degree of carbon reduction. Based on results obtained from this study, suggestions were made on smooth operations of smelt-reduction of the briquettes by using EAF or induction furnace with large scales.

  • 3086.
    Yang, Qixing
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Minerals and Metallurgical Engineering.
    Xue, Peng
    School of Metallurgical and Ecological Engineering, University of Science and Technology, Beijing.
    He, Dogfeng
    Department of Ferrous Metallurgy, School of Metallurgical and Ecological Engineering, University of Science and Technology Beijing.
    Xu, An-Jun
    State Key Laboratory of Advanced Metallurgy, University of Science and Technology Beijing, School of Metallurgical and Ecological Engineering, University of Science and Technology, Beijing , Department of Ferrous Metallurgy, School of Metallurgical and Ecological Engineering, University of Science and Technology Beijing.
    Engström, Fredrik
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Minerals and Metallurgical Engineering.
    Han, Fenglan
    School of Material Science & Engineering, Beifang University of Nationality, Yinchuan, Ningxia.
    Chen, Yuhong
    School of Material Science & Engineering, Beifang University of Nationality, Yinchuan, Ningxia.
    Björkman, Bo
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Minerals and Metallurgical Engineering.
    Studies of using slags from ore based steelmaking to produce sulphoaluminate belite cement with reduced CO2 emission2015In: Proceedings of the 6th International Congress on the Science and Technology of Steelmaking: ICS 2015, Beijing, China; 12 - 14 May 2015 / [ed] X. Wang, The Chinese Society for Metals , 2015, p. 962-965Conference paper (Refereed)
    Abstract [en]

    The aim of the present studies is to examine the potential for using basic oxygen furnace, ladle and blast furnace slags from Swedish works of ore based steelmaking in production of clinkers for sulphoaluminate belite cement. The slags and chemicals were mixed to form briquettes for burning at 1300 . Samples of the clinker briquettes obtained were characterized by different methods. The sulphoaluminate and other phases in the clinker samples were detected by XRD. These and other results showed that the slags can be used in the cement, stabilizing belite phase in the clinkers and enhancing heat fluxes or the degrees of hydration measured in the early, 24-hour period for the clinkers, thus to allow for more sustainable steel and cement production.

  • 3087. Yang, W.
    et al.
    Fredriksson, Hasse
    KTH, School of Industrial Engineering and Management (ITM), Materials Science and Engineering.
    Ji, S.
    Halo formation of Zn-Al alloys under conventional solidification and intensive convection solidification2017In: Journal of Alloys and Compounds, ISSN 0925-8388, E-ISSN 1873-4669, Vol. 696, p. 460-469Article in journal (Refereed)
    Abstract [en]

    A halo occurred usually as an envelope of one phase around a primary phase in many alloys after solidification. Its formation mechanism was investigated for hypoeutectic, eutectic and hypereutectic compositions of Zn-Al alloys under conventional solidification and under intensive convection solidification. It was found that the Zn-rich halos occurred in the surroundings of the Al-rich primary phase for the hypereutectic Zn-Al alloys at Al>5 wt% and no halos occurred for the hypoeutectic and eutectic Zn-Al alloys at Al≤5 wt% under conventional solidification. However, the Zn-rich halos were completely absent from the Al-rich phase because of the uniform temperature distribution and enhanced mass transport under intensive convection solidification. Once the intensive convection was interrupted during solidification for the solid-liquid co-existing melt, a halo was formed on the surface of the existing Al-rich phase created either during the primary solidification or the eutectic solidification. Therefore, it was concluded that the halo formation should be a growth-dominant phenomenon not a nucleation-dominant phenomenon. And, the interaction among the solid phases and the liquid phase was responsible for the halo formation, in which the difference in the elasticity modulus and the density of the different phases resulted in the variation of strain energy in the individual phase.

  • 3088.
    Yang, Weihong
    et al.
    KTH, Superseded Departments, Materials Science and Engineering.
    Blasiak, Wlodzimierz
    KTH, Superseded Departments, Materials Science and Engineering.
    Combustion performance and numerical simulation of a high-temperature air-LPG flame on a regenerative burner2004In: Scandinavian journal of metallurgy, ISSN 0371-0459, E-ISSN 1600-0692, Vol. 33, no 2, p. 113-120Article in journal (Refereed)
    Abstract [en]

    High-temperature air combustion is attracting great interest in the metallurgical industry lately as its claimed benefits include large energy saving, low air emissions, increased product quality and increased productivity. This paper presents a numerical study of combustion performance in a semi-industrial test furnace equipped with a regenerative burner and with a conventional turbulent jet burner. The numerical calculation is also validated by experiment. In this regard, flow field was calculated with k-epsilon turbulence model, the model of combustion employed the eddy dissipation concept with a two-step mechanism to describe chemical reactions; radiation was handled using the discrete transfer method. The results indicate that equipping a furnace with high-cycle regenerative burner systems can provide more uniform gas temperature profiles, a higher energy utilizing efficiency, a low NOx emission, a larger flame, the low maximum local heat release and the possibility of low combustion noise.

  • 3089.
    Yang, Weihong
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Materials Science and Engineering, Energy and Furnace Technology.
    Ponzio, Anna
    KTH, School of Industrial Engineering and Management (ITM), Materials Science and Engineering, Energy and Furnace Technology.
    Lucas, Carlos
    KTH, School of Industrial Engineering and Management (ITM), Materials Science and Engineering, Energy and Furnace Technology.
    Blaslak, Wlodzmierz
    KTH, School of Industrial Engineering and Management (ITM), Materials Science and Engineering, Energy and Furnace Technology.
    Performance analysis of a fixed-bed biomass gasifier using high-temperature air2006In: Fuel processing technology, ISSN 0378-3820, E-ISSN 1873-7188, Vol. 87, no 3, p. 235-245Article in journal (Refereed)
    Abstract [en]

    Gasification of biomass using high-temperature agents (air/steam) has been proven to have many features superior to those of conventional gasification using low-temperature agents. In this work, an experimental fixed-bed gasifier is utilized to investigate the gasification of biomass using high-temperature air up to 1473 K. A mathematical model has been formulated for the prediction of the main chemical and physical processes and is used to study the influence of temperature, oxygen concentration and flow rate of the feed gas. Predicted gas species concentration profiles and their maximum values are in reasonable agreements with the measurements. The results show that: (a) When the temperature of feed gas is increased, a higher gasification rate, a higher ignition front rate, and higher molar fractions of fuel gases (CO, H-2 and CmHn), thus a higher LHV are obtained. (b) Increased oxygen concentration leads to higher peak values of the fuel gas concentrations, a higher gasification rate, and a larger ignition front rate.

  • 3090. Yang, Wenchao
    et al.
    Fredriksson, Hasse
    KTH, School of Industrial Engineering and Management (ITM), Materials Science and Engineering, Casting of Metals.
    Ji, Shouxun
    Halo formation of Zn-Al alloys under conventional solidification and intensive convection solidification2017In: Journal of Alloys and Compounds, ISSN 0925-8388, E-ISSN 1873-4669, Vol. 696, p. 460-469Article in journal (Refereed)
    Abstract [en]

    A halo occurred usually as an envelope of one phase around a primary phase in many alloys after solidification. Its formation mechanism was investigated for hypoeutectic, eutectic and hypereutectic compositions of Zn-Al alloys under conventional solidification and under intensive convection solidification. It was found that the Zn-rich halos occurred in the surroundings of the Al-rich primary phase for the hypereutectic Zn-Al alloys at Al> 5 wt% and no halos occurred for the hypoeutectic and eutectic Zn-Al alloys at Al <= 5 wt% under conventional solidification. However, the Zn-rich halos were completely absent from the Al-rich phase because of the uniform temperature distribution and enhanced mass transport under intensive convection solidification. Once the intensive convection was interrupted during solidification for the solid-liquid co-existing melt, a halo was formed on the surface of the existing Al-rich phase created either during the primary solidification or the eutectic solidification. Therefore, it was concluded that the halo formation should be a growth-dominant phenomenon not a nucleationdominant phenomenon. And, the interaction among the solid phases and the liquid phase was responsible for the halo formation, in which the difference in the elasticity modulus and the density of the different phases resulted in the variation of strain energy in the individual phase.

  • 3091.
    Yang, Yang
    KTH, School of Industrial Engineering and Management (ITM), Materials Science and Engineering, Materials Process Science.
    Equilibrium phase relationships in the CaO-MgO-SiO2-Cr2O3 slags2012Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
  • 3092.
    Yang, Yang
    KTH, School of Industrial Engineering and Management (ITM), Materials Science and Engineering, Computational Thermodynamics.
    Investigation of vanadium-containing oxide systems: CALPHAD and experiments2016Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Fundamental studies on thermodynamic properties of vanadium-containing oxides systems are essential to understand practical vanadium metallurgical process. The CALPHAD technique is here applied to the thermodynamic modelling of the V-O, Ca-V-O and Ti-V-O systems. The compound energy formalism is used for all the solution phases. All optimization processes and calculations are performed using the Thermo-Calc software package. The present work attempts to develop a self-consistent thermodynamic database of all phases in the studied systems. The obtained datasets can be used to calculate thermodynamic properties, stable as well as metastable phase equilibria and driving forces for oxidation etc.

    Steelmaking slag is an important secondary source for vanadium extraction. The phase relationships and vanadium distribution in the CaO-SiO2-MgO-V2O3-Al2O3 synthetic slags, whose compositions were chosen based on the relevance to the steel producers, are also studied. Phase equilibria in the temperature range of 1773 to 1823 K at oxygen partial pressure of 10-10 bar and 0.21 bar were characterized.

    An investigation of the volatilization of vanadium oxide was also carried out in the present work. Isothermal evaporation of vanadium pentoxide in the temperature range between 1723 and 1873 K was investigated by Thermogravimetric Analysis under different oxygen partial pressures, viz. oxygen, air or CO2. The Arrhenius activation energy for the evaporation reaction in various atmospheres was calculated from the experimental results. A mathematical model was developed to describe the kinetics of the evaporation process. Evaporation coefficients and enthalpies in various atmospheres were also estimated. The present results may have some implications in recovering vanadium from different vanadium-bearing sources.

  • 3093.
    Yang, Yang
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Materials Science and Engineering, Computational Thermodynamics.
    Mao, Huahai
    KTH, School of Industrial Engineering and Management (ITM), Materials Science and Engineering, Computational Thermodynamics.
    Chen, Hai-Lin
    Thermo-Calc Software AB, Norra Stationsgatan 93, 113 64 Stockholm, Sweden..
    An assessment of the Ti-V-O systemArticle in journal (Other academic)
  • 3094.
    Yang, Yang
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Materials Science and Engineering, Computational Thermodynamics.
    Mao, Huahai
    KTH, School of Industrial Engineering and Management (ITM), Materials Science and Engineering, Computational Thermodynamics.
    Selleby, Malin
    KTH, School of Industrial Engineering and Management (ITM), Materials Science and Engineering, Computational Thermodynamics.
    An assessment of the Ca-V-O system2017In: Calphad, ISSN 0364-5916, E-ISSN 1873-2984, p. 29-40Article in journal (Refereed)
    Abstract [en]

    The Ca-V-O system is studied with an emphasis on the following oxide sub-systems: CaO-V2O5, CaO-V2O3, V2O5-CaV2O5 and CaO-V2O5-VO2. The aim of the present assessment is to obtain a thermodynamic description of the Ca-V-O system. The compound energy formalism was used to describe the liquid by applying the ionic two-sublattice model and the β-bronze phase CaxV2O5 (0.17≤x≤0.33) using a three-sublattice model. Phase equilibria and thermodynamic properties were critically evaluated using the CALPHAD approach and a consistent set of thermodynamic model parameters was obtained. Satisfactory agreement between calculated and experimental values is achieved.

  • 3095.
    Yang, Yang
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Materials Science and Engineering.
    Mao, Huahai
    KTH, School of Industrial Engineering and Management (ITM), Materials Science and Engineering, Computational Thermodynamics. Thermo-Calc Software AB, Norra Stationsgatan 93, Stockholm, Sweden.
    Selleby, Malin
    KTH, School of Industrial Engineering and Management (ITM), Materials Science and Engineering, Computational Thermodynamics.
    Thermodynamic assessment of the V-O system2015In: Calphad, ISSN 0364-5916, E-ISSN 1873-2984, Vol. 51, p. 144-160Article in journal (Refereed)
    Abstract [en]

    The V-O system was thermodynamically assessed using the CALPHAD method. The available experimental data on thermodynamic and thermochemical properties as well as phase diagram information were critically examined and a self-consistent set of thermodynamic parameters was obtained. In total 20 phases were included in this binary system. Five among them were treated as solid solution phases within the framework of the compound energy formalism. The halite phase was modeled as (V,V+2,V+3,Va)<inf>1</inf>(O-2,Va)<inf>1</inf> covering the solubility of both V and O. Thermodynamic descriptions of two different models for the corundum phase are presented, one of which is more complex to correctly take the defect mechanisms into account. The liquid phase was described by the ionic two-sublattice model with the formula (V+2)<inf>P</inf>(O-2,Va-Q, VO<inf>1.5</inf>,VO<inf>2</inf>, VO<inf>2.5</inf>)<inf>Q</inf>. The stoichiometric Magnéli phases V<inf>n</inf>O<inf>2n-1</inf> (n is an integer between 4 and 8) were modeled as (V+3)<inf>2</inf>(V+4)<inf>n-2</inf>(O-2)<inf>2n-1</inf>. Using the present thermodynamic description reliable experimental phase diagram, thermodynamic and thermochemical data were well reproduced.

  • 3096.
    Yang, Yang
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Materials Science and Engineering.
    Teng, Lidong
    KTH, School of Industrial Engineering and Management (ITM), Materials Science and Engineering.
    Seetharaman, Seshadri
    KTH, School of Industrial Engineering and Management (ITM), Materials Science and Engineering, Materials Process Science.
    Experimental Study of Phase Equilibria in CaO-SiO2-MgO-Al2O3-V2O3 Slags2014In: Steel Research International, ISSN 1611-3683, E-ISSN 1869-344X, Vol. 85, no 12, p. 1588-1596Article in journal (Refereed)
    Abstract [en]

    Thermodynamic data with regard to slags containing vanadium oxide are scarce and scattered. In the present study, the classic gas-slag equilibrium technique has been adopted to investigate the phase relationships in the CaO-SiO2-MgO-Al2O3-V2O3 slags. The phase equilibria in the slag systems in the temperature range of 1773-1823K (1500-1550 degrees C) at oxygen partial pressures of 10(-5) Pa and 0.21 x 10(5) Pa were characterized. CaVO3 was precipitated in samples with basicity 1.5 and 1.8 treated in air at 1773 K (1550 degrees C) while all vanadium was dissolved in equilibrium phases in samples treated at oxygen partial pressure of 10(-5) Pa. Vanadium distribution between the slags and solid Pt and phase compositions were analyzed using scanning electron microscopy (SEM), energy dispersive spectrometer (EDS), and X-ray diffractomer (XRD) techniques. The effects of temperature, oxygen partial pressure, and slag basicity on the phase compositions in the slags are presented. Activities of VO1.5 were also calculated using the value of vanadium activity in the Pt-V alloy.

  • 3097.
    Yang, Yang
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Materials Science and Engineering, Materials Process Science.
    Teng, Lidong
    KTH, School of Industrial Engineering and Management (ITM), Materials Science and Engineering, Materials Process Science.
    Seetharaman, Seshadri
    KTH, School of Industrial Engineering and Management (ITM), Materials Science and Engineering, Materials Process Science.
    Kinetic Studies on Evaporation of Liquid Vanadium Oxide, VO (x) (Where x=4 or 5)2012In: Metallurgical and materials transactions. B, process metallurgy and materials processing science, ISSN 1073-5615, E-ISSN 1543-1916, Vol. 43, no 6, p. 1684-1691Article in journal (Refereed)
    Abstract [en]

    As part of the Swedish National Eco-steel project, the present work was carried out with a view to study the evaporation of vanadium as V2O5 with a focus on the health hazards. The evaporation rate was followed by monitoring the mass loss from liquid V2O5 melts by thermogravimetric analysis (TGA) in the temperature range 1723 K to 1873 K (1450 A degrees C to 1600 A degrees C). The studies were carried out under three different oxygen partial pressures, viz, oxygen, air, or CO2. The experiments were carried out in the isothermal mode. The Arrhenius activation energies for the evaporation reaction in different atmospheres were calculated from the results. A mathematical model was developed in order to describe the kinetics of the evaporation process. Good agreement could be achieved between the mathematical model and the experimental results. Evaporation coefficients and enthalpies in different atmospheres were also estimated. The present results may also have implications in recovering vanadium values from different vanadium sources.

  • 3098.
    Yang, Ying
    KTH, School of Industrial Engineering and Management (ITM), Materials Science and Engineering, Applied Process Metallurgy.
    Inclusion Motion under a Swirl Flow in the Continuous Casting Process and Wire Feeding in the Induction Furnace2015Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    The thesis includes the studies of two phenomena related to continuous casting. One subject is the inclusion motion in the submerged entry nozzle (SEN) and mold when using a swirl flow. The swirl flow is generated in a SEN by using an electromagnetic swirl flow generator (EMSFG). The other subject is focused on FeSiRE particles (powder) that are added into the molten steel by using a wire feeding method, which in the future could be used in a continuous casting mold.

    Firstly, two kinds of a full type and a half type EMSFG were designed based on mathematical modeling. Then, the distributions of the magnetic flux intensity and the Lorentz force were obtained for two types of EMSFG devices. Based on the results of the Lorentz force, the flow field, temperature field and inclusion motion in the SEN and the mold were studied by using a full type and a half type EMSFG. Moreover, a comparison from the above aspects was investigated between a full type EMSFG and a half type EMSFG. In addition, the effect of different inclusion parameters such as the densities, sizes and boundary conditions, on the inclusion behavior was studied. It was found that light Al2O inclusion moves towards the rotational center by a centrifugal force and that a swirl flow prevents nozzle clogging. The heavy CeO inclusion more or less moves outwards towards the SEN wall and they may stick to the wall. It was also found that the inclusion separation to a mold meniscus increased and that the inclusions being trapped into a solidified shell decreased when using a swirl flow compared to when not using a swirl flow.

    A study of a wire feeding into molten steel in an induction furnace was done to determine the potential to implement wire feeding into a mold in the future. A major difference compared to a traditional solid wire is that the wire contains particles (powder). Firstly of all, the wire melting behavior in the molten steel was studied. More specially, the influence of the different wire materials (aluminum, copper and 316L stainless steel wires) on the dissolution time in the molten steel was modeled. Moreover, these simulation results were compared to experimental results. In addition, the FeSiRE particle (powder) motion in the induction furnace was also simulated. The results showed that the copper wire is more suitable to apply in the continuous casting mold when a small addition and a lower wire feeding speed are used. Conversely, if a large amount and a higher feeding speed are needed, the aluminum wire may be recommended for injections in the mold. The results also indicated that the thermal properties of particle (powder) have an influence on the wire melting behavior in the molten steel.

    The full text will be freely available from 2025-11-27 10:00
  • 3099.
    Yang, Ying
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Materials Science and Engineering, Applied Process Metallurgy.
    Juneblad Målar, Oscar
    KTH, School of Industrial Engineering and Management (ITM), Materials Science and Engineering, Applied Process Metallurgy.
    Ersson, Mikael
    KTH, School of Industrial Engineering and Management (ITM), Materials Science and Engineering, Applied Process Metallurgy.
    Nakajima, Keiji
    KTH, School of Industrial Engineering and Management (ITM), Materials Science and Engineering, Applied Process Metallurgy.
    Jönsson, Pär
    KTH, School of Industrial Engineering and Management (ITM), Materials Science and Engineering, Applied Process Metallurgy.
    The Wire Feeding and Melting behavior in the Induction FurnaceManuscript (preprint) (Other academic)
  • 3100.
    Yang, Ying
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Materials Science and Engineering, Applied Process Metallurgy.
    Jönsson, Pär
    KTH, School of Industrial Engineering and Management (ITM), Materials Science and Engineering, Applied Process Metallurgy.
    Ersson, Mikael
    KTH, School of Industrial Engineering and Management (ITM), Materials Science and Engineering, Applied Process Metallurgy.
    Su, Zhijian
    He, Jicheng
    Nakajima, Keiji
    KTH, School of Industrial Engineering and Management (ITM), Materials Science and Engineering, Applied Process Metallurgy.
    The Influence of Swirl Flow on the Flow Field, Temperature Field and Inclusion Behavior When Using a Half Type Electromagnetic Swirl Flow Generator in a Submerged Entry Nozzle and Mold2015In: Steel Research International, ISSN 1611-3683, E-ISSN 1869-344X, Vol. 86, no 11, p. 1312-1327Article in journal (Refereed)
    Abstract [en]

    In the preceding work, the inclusion behavior in a submerged entry nozzle (SEN) and mold induced by using a swirl flow has been investigated. The results showed that a swirl flow can effectively promote the inclusions removal to the meniscus as well as reduce the inclusions entrapment at the solidified shell wall. Moreover, that the swirl flow was generated by using a full type electromagnetic swirl flow generator (EMSFG). In the present work, a kind of a half type EMSFG was investigated, since it is easier to implement in a production scale. The influence of the stirrer on the fluid flow, heat transfer, and inclusion behavior in the SEN and mold was studied. Furthermore, a comparison between these two types of EMSFG from the aspects of flow field, temperature field, and inclusion behavior was done. In addition, the effect of different magnetomotive forces, inclusion sizes, densities as well as boundary conditions on the inclusion behavior was studied. The results show that the effect of a half type EMSFG (88000 AT) on the molten steel is very close to a full type case (44000 AT). More specifically, the flow pattern, temperature distribution as well as inclusion behavior in the SEN and mold look very similar. Also, it was found that from the viewpoints of the inclusions separation to the mold meniscus and the inclusions trapping at the solidified shell wall, better results could be obtained for a “Trap” boundary condition when using half type EMSFGs.

59606162636465 3051 - 3100 of 3315
CiteExportLink to result list
Permanent link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf