- Effect of Pre-cold Rolling-Induced Twins and Subsequent Precipitated omega-Phase on Mechanical Properties in a beta-Type Ti-Mo Alloy
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- 论文类型: 期刊论文
- 发表时间: 2018-06-01
- 发表刊物: ACTA METALLURGICA SINICA-ENGLISH LETTERS
- 收录刊物: SCIE
- 卷号: 31
- 期号: 6
- 页面范围: 604-614
- ISSN号: 1006-7191
- 关键字: beta-Type titanium alloy; Pre-cold rolling; Twinning deformation; Isothermal omega-phase; Strength-ductility
- 摘要: This paper reported an effectiveness of pre-cold rolling-induced {332}<113> twins combined with subsequent isothermal x-phase formation for enhancement of uniform elongation in a beta-type Ti-15Mo alloy with high yield strength level. Mechanical {332}<113? twins were induced by cold rolling with an thickness reduction of 5%, which had little effect on x-phase precipitation after aging at 573 K for 3.6 ks. Twinning after the cold rolling was further activated during tensile deformation, even with the presence of isothermal omega-phase. This combination of twins and omega-phase enhanced uniform elongation from 0 to 9% at yield strength level of 890 MPa. The high yield strength was mainly dominated by dislocation slip due to the isothermal x-phase formation, and early onset of plastic instability after yielding was hindered due to the pre-cold rolling-induced twins. Dynamic microstructural refinement was induced by further twinning activation during deformation, which resulted in high work hardening rate corresponding enhancement of uniform elongation.