亚稳态β钛合金的成分设计、变形机制与力学性能

Composition design, deformation mechanism and mechanical properties of metastable β titanium alloy

摘要:

本文介绍了当前TWIP/TRIP钛合金的研究现状和设计方法,并且统计了TWIP/TRIP钛合金中发生双孪晶{332}<113>、{112}<111>的β晶粒尺寸大小、屈服强度和加工硬化率。讨论了Bo-Md图在多组元钛合金设计上的应用和局限性,特别是析出不同二次相(α相与ω相)对基体β相稳定性的影响。从基体β相稳定性、析出相、β晶粒尺寸和晶体学取向三方面归纳了影响亚稳态β钛合金TWIP/TRIP变形机制的因素,并对其中存在的一些问题和不足进行了分析,简要总结了双孪晶机制对钛合金力学性能的影响。通过综述最新的研究进展及相关问题,对未来高强韧钛合金发展提出新见解。

Abstract:

This article introduces the current research progress and theoretical basis of designing the TWIP / TRIP (TRIP: transformation induced plasticity; TWIP: twin induced plasticity) metastable β titanium alloys, and summarizes β-grain sizes, yield strength and work hardening capability achieved in the double twined {332} <113> and {112} <111> metastable β titanium alloys. The application and limitation of Bo-Md diagram in the design of multi-component titanium alloys are further discussed, especially the effect of different secondary phases (α-phase and ω-phase) on the stability of the matrix β-phase. The factors that influence the deformation mechanisms of TWIP / TRIP metastable β titanium alloys are emphasized in terms of the matrix β phase stability, precipitated phases, β-grain sizes and crystallographic orientations, in which the current deficiencies of this field are analyzed. Furthermore, the effect of double twinning mechanisms on the mechanical properties of titanium alloys is briefly discussed as well. Finally, by summarizing the research progress and related issues, this article conveys the new insights into the development of high-strength and tough titanium alloys.