Microstructural homogeneity and mechanical behavior of a selective laser melted Ti-35Nb alloy produced from an elemental powder mixture

Jincheng Wang, Yujing Liu, Chirag Dhirajlal Rabadia, Shun-Xing Liang, Timothy Barry Sercombe, Lai-Chang Zhang

Research output: Contribution to journalArticlepeer-review

23 Citations (Scopus)

Abstract

Although using elemental powder mixtures may provide broad alloy selection at low cost for selective laser melting (SLM), there is still a concern on the resultant microstructural and chemical homogeneity of the produced parts. Hence, this work investigates the microstructure and mechanical properties of a SLM-produced Ti-35Nb composite (in wt%) using elemental powder. The microstructural characteristics including p phase, undissolved Nb particles and chemical homogeneity were detailed investigated. Nanoindentation revealed the presence of relatively soft undissolved Nb particles and weak interface bonding around Nb-rich regions in as-SLMed samples. Solid-solution treatment can not only improve chemical homogeneity but also enhance bonding through grain boundary strengthening, resulting in similar to 43 % increase in tensile elongation for the heat-treated Ti-35Nb compared to the as-SLMed counter-part. The analyses of tensile fractures and shear bands further confirmed the correlation between the different phases and the ductility of Ti-35Nb. In particular, the weak bonding between undissolved Nb and the matrix in the as-SLMed sample reduces its ductility while the p grains in solid-solution treated Ti-Nb alloy can induce a relatively stable plastic flow therefore better ductility. This work sheds insight into the understanding of homogenization of microstructure and phases of SLM-produced alloys from an elemental powder mixture. (C) 2021 Published by Elsevier Ltd on behalf of The editorial office of Journal of Materials Science & Technology.

Original languageEnglish
Pages (from-to)221-233
Number of pages13
JournalJournal of Materials Science and Technology
Volume61
DOIs
Publication statusPublished - 20 Jan 2021

Fingerprint

Dive into the research topics of 'Microstructural homogeneity and mechanical behavior of a selective laser melted Ti-35Nb alloy produced from an elemental powder mixture'. Together they form a unique fingerprint.

Cite this