Characterization of Metal Powders Produced by Two Gas Atomizing Methods for Thermal Spraying Applications
Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
This thesis work is focused on the influence of process parameters during gas atomization on the thermal spraying properties of a Ni-Cr-B-Si hardfacing alloy. The metal powder alloy, known as 1-60-20, is produced by Höganäs AB. There have been problems with insufficient fusing during flame spraying of this particular alloy sometimes, even though the chemical composition is always within spec. This has lead to a theory that the difference in performance is caused by differences in parameters during gas atomization.
Several gas-gas and gas-water atomizations with varying parameters were performed at the Höganäs Pilot Centre. The powder samples were then analyzed by sieving, scanning electron microscopy, x-ray diffraction and finally tested by powder welding.
The results show that by increasing the cooling rate during gas atomization the formation of unstable Ni-borides is possible for this alloy.
If these Ni-borides will enhance the fusing properties of the alloy is unknown. According to the literature studied, it should however improve the fusing properties.
Place, publisher, year, edition, pages
2015. , 45 p.
Powder metallurgy, Gas atomization, Thermal Spraying, Ni-Si-B, Ni-boride
Metallurgy and Metallic Materials
IdentifiersURN: urn:nbn:se:kth:diva-180352OAI: oai:DiVA.org:kth-180352DiVA: diva2:893325
Subject / course
Materials and Process Design
Master of Science in Engineering - Materials Design and Engineering
Brabie, Liviu, Dr
Eliasson, Anders, Dr