Oxygen-induced refinement of α precipitates in an aged metastable β Ti-15-333 alloy

SCRIPTA MATERIALIA

卷:205

Article

Chou, Kathleen¹  Neill, Owen²  Marquis, Emmanuelle A.¹ 

[1] Univ Michigan, Dept Mat Sci & Engn, Ann Arbor, MI 48109 USA

[2] Univ Michigan, Dept Earth & Environm Sci, Ann Arbor, MI 48103 USA

关键词: Titanium alloys;    Phase transformations;    Precipitation;    Compression test;    Oxygen;   

DOI  :  10.1016/j.scriptamat.2021.114206

来源: Elsevier

【 摘 要 】

Increasing the strength of aged metastable beta titanium alloys through refinement of intragranular alpha precipitates has been previously demonstrated using heterogeneous nucleation on structural and compositional non-uniformities. Here, we show that elevated oxygen levels (up to 1.7 at. %) can also induce alpha phase refinement during ageing of a beta Ti-15-333 alloy, providing an additional pathway to obtain fine alpha laths. Moreover, oxygen-induced refinement combined with omega-assisted alpha nucleation resulted in significantly reduced alpha sizes of similar to 50 nm. The finer alpha precipitates obtained with higher oxygen concentrations resulted in increased compressive yield strengths during micropillar compression compared to specimens without oxygen. These findings highlight the use of high oxygen contents to improve alpha microstructural refinement and precipitation strengthening in beta Ti alloys. (C) 2021 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

【 授权许可】

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