Change search
CiteExportLink to record
Permanent link

Direct 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
Characterization of Heat Treated LMwD Ti-6Al-4V to Study the Effect of Cooling Rate on Microstructure and Mechanical Properties
Luleå University of Technology, Department of Engineering Sciences and Mathematics.
2019 (English)Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
Abstract [en]

In this work, the influence of different cooling rates (5, 20, 50 and 100 °C/s) on the microstructure and mechanical properties of Laser Metal Wire Deposited (LMwD) Ti-6Al-4V was investigated, this was done using a thermal-mechanical physical simulation system (Gleeble 3800, DSI). Two different soak times above β transus (held at 1100 °C), 5 and 40 s, were used and after cooling to 150 °C, the samples were tensile tested. The samples were characterized with optical microscopy (OM) and scanning electron microscopy (SEM) and hardness testing. The results were then compared, both with each other and with two reference samples, that were only heated to 150 °C and then tensile tested. It was found that for the lowest cooling rate, 5 °C/s, the microstructure had transformed from a basketweave α microstructure to a colony α microstructure in the center of the specimen waist where heating was most efficient. Ultimate tensile strength (UTS) was found to be in the range of 858 – 977 MPa, with the highest average being recorded for the reference samples, similar results were noted for the strain, with a range of  ⁓5 – 14 %, where the highest recorded average was for the reference samples. However, the extensometer used was not optimized for this kind of test, therefore percent reduction of area (RA) measurements were performed. The RA measurements produced a significantly different result than that obtained from the testing, a large scatter in the ductility was found, possibly due to thermal instability that occurred during testing. Overall, the microstructure appears to be relatively stable over the cooling range of 20 - 100 °C/s, no major differences were observed, the microstructure consisted of a homogeneous basketweave α microstructure, with little to no change in the measured average α lath thickness.

Place, publisher, year, edition, pages
2019. , p. 56
Keywords [en]
Ti-6Al-4V, LMwD, Characterization, Alpha Laths
National Category
Metallurgy and Metallic Materials
Identifiers
URN: urn:nbn:se:ltu:diva-75979OAI: oai:DiVA.org:ltu-75979DiVA, id: diva2:1350940
External cooperation
GKN Aerospace Sweden AB
Educational program
Materials Engineering, master's level
Supervisors
Examiners
Available from: 2019-09-13 Created: 2019-09-12 Last updated: 2019-09-13Bibliographically approved

Open Access in DiVA

fulltext(7952 kB)14 downloads
File information
File name FULLTEXT01.pdfFile size 7952 kBChecksum SHA-512
31f8f2b6d2e77931b591b1385f89fb66072d65cf832c27e373f2f9eb00b871270ad1a2843d80144093cc98b4d8899c47ea88803604c0f8de2a1c021646824a9e
Type fulltextMimetype application/pdf

Search in DiVA

By author/editor
Edin, Emil
By organisation
Department of Engineering Sciences and Mathematics
Metallurgy and Metallic Materials

Search outside of DiVA

GoogleGoogle Scholar
Total: 14 downloads
The number of downloads is the sum of all downloads of full texts. It may include eg previous versions that are now no longer available

urn-nbn

Altmetric score

urn-nbn
Total: 25 hits
CiteExportLink to record
Permanent link

Direct 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