Effect of heat treatment on microstructure and properties of selective laser melting Co-Cr Alloy

doi:10.13251/j.issn.0254-6051.2023.01.005

Abstract

Abstract: In order to clarify the effect of heat treatment on microstructure and properties of selective laser melting (SLM) cobalt-chromium alloy, the changes of microstructure and properties of the cobalt-chromium alloy SLMed under laser power of 290 W and scanning speed of 950 mm/s before and after heat treatment of heating at 1150 ℃ for 6 h were investigated by means of OM, SEM, XRD, EBSD, EPMA, mechanical properties and electrochemical corrosion test. The results show that after heat treatment, the typical molten pool morphology disappears, and obvious carbide precipitates can be observed in the grain boundaries and intergrains, meanwhile, the grains change from coarse columnar to fine equiaxed grains, the corrosion resistance decreases, the hardness changes little, the elongation increases by about 30%. Finally, through heat treatment, uniform microstructure can be obtained, the volume fraction of γ phase can be increased, and the plasticity can be improved, but the electrochemical corrosion performance is reduced.

Key words: selective laser melting, cobalt-chromium alloy, heat treatment, microstructure, mechanical properties

CLC Number:

TN249

Deng Yuhua, Li Zhenhua, Yao Bibo, Teng Baoren, Li hao. Effect of heat treatment on microstructure and properties of selective laser melting Co-Cr Alloy[J]. Heat Treatment of Metals, 2023, 48(1): 23-28.

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