Anisotropic microstructure and mechanical properties of additively manufactured Co-Cr-Mo alloy using selective electron beam melting for orthopedic implants

MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING

卷:765

Article

Xiang, D. D.^1,3  Wang, P.²  Tan, X. P.¹  Chandra, S.¹  Wang, C.¹  Nai, M. L. S.²  Tor, S. B.¹  Liu, W. Q.³  Liu, E.¹ 

[1] Nanyang Technol Univ, Singapore Ctr 3D Printing, Sch Mech & Aerosp Engn, 50 Nanyang Ave, Singapore 639798, Singapore

[2] Singapore Inst Mfg Technol, 73 Nanyang Dr, Singapore 637662, Singapore

[3] Tsinghua Univ, Dept Mech Engn, State Key Lab Tribol, Beijing 100084, Peoples R China

关键词: Additive manufacturing;    3D printing;    Selective electron beam melting;    Co-Cr-Mo;    Anisotropy;    Implant;   

DOI  :  10.1016/j.msea.2019.138270

来源: Elsevier

【 摘 要 】

Co-Cr-Mo alloy is used extensively for orthopedic implant applications. In this work, anisotropy in microstructure and mechanical properties of additively manufactured Co-Cr-Mo alloy by selective electron beam melting (SEBM) has been investigated. Experimental results show that the SEBM-built Co-Cr-Mo parts along the build direction would be preferred over that of the non-build direction in strength and elongation. Strong anisotropy in tensile properties was found for the SEBM-built Co-Cr-Mo parts in two different directions. The microstructure of SEBM-built Co-Cr-Mo alloys consists of face-centered cubic columnar grains with the < 001 > preferred orientation and continuous thin carbide films at the grain boundaries. Columnar grains are supposed to be the basic microstructure feature that results in poor mechanical performance in the non-build direction. However, continuous thin carbide films at columnar grain boundaries severely exaggerate the anisotropic characteristics, which is the dominant reason for anisotropy. It is suggested that the SEBM-built Co-Cr-Mo along the build direction is expected to be suitable for load-bearing orthopedic implants.

【 授权许可】

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