Cryogenic treatment on Ti6Al4V alloy fabricated by electron beam melting: microstructure and mechanical properties

In this study, the effect of cryogenic treatment at -196 degrees C with six different soaking times on the microstructure and mechanical properties of Ti6Al4V alloy fabricated using electron beam melting (EBM) were systematically investigated. The results show that the microstructure of the as-fabricated specimen is a typical Widmanstatten structure. The cryogenic treatment process effectively refines the lamellar a phase remaining in the asfabricated microstructure. Moreover, the thickness of the lamellar a phase decreases with the increase of the soaking time. In comparison to the as-fabricated specimen, the tensile and yield strengths, as well as elongation of the cryogenic treated specimens rise rapidly with the increase of soaking time until 48 h, which increases 18.64%, 18.65%, and 91.67%, respectively. In addition, the number of fatigue cycles of the specimen cryogenic treated for 48 h increases by 115.22% compared with the as-fabricated one.(c) 2022 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).