TC17钛合金热变形过程中片状组织球化演变及Burgers关系的破坏  

Globularization Evolution of Lamellar Microstructure and Destruction of Burgers Orientation Relationship for TC17 Titanium Alloy during Hot Deformation

作　　者：贾志强[1] 曾卫东[1] 王凯旋[1] 

机构地区：[1]西北工业大学凝固技术国家重点实验室,陕西西安710072

出　　处：《稀有金属材料与工程》2017年第10期2895-2899,共5页Rare Metal Materials and Engineering

基　　金：教育部博士点基金(20136102110034);新世纪优秀人才支持计划(NCET-07-0696)

摘　　要：采用EBSD技术研究了TC17钛合金片状组织在热变形过程中的球化演变规律,并对比分析了变形前后α相与β相间Burgers关系的变化。结果表明,热变形导致β相发生明显的动态再结晶。变形初期,片状组织内部首先在动态回复作用下形成位错亚结构,此时各亚结构间的亚晶界均为小角度晶界;随着变形的增大,亚晶界转化为大角度晶界导致片状α的破裂;破碎α相的相界再通过扩散作用继续迁移,最终实现α相的球化。热变形在改变片状组织形貌和稳定性的同时,也破坏了片状组织中α相和β相间严格的Burgers关系,热变形过程中,柱滑移和其他滑移系或孪晶系的启动是造成α相与β相间严格Burgers关系破坏的根本原因。The microstructure evolution and the change of Burgers orientation relationship between α and β phase of TC17 titanium alloy with initial lamellar microstructure were researched by EBSD. The results show that dynamic recrystallization of β phase occurs during the hot deformation process. Meanwhile, the dynamic globularization of α phase includes the formation of subboundary and the fragmentation of α phase. The fragmentized α phase eventually transforms to globularized particle. In addition, the strict Burgers orientation relationship between α and β phase is destroyed, due to the activation of prismatic slip system and other slip or twin systems.

关 键 词：TC17钛合金 Burgers关系 显微组织 EBSD 小角度晶界 大角度晶界 

分 类 号：TG146.23[一般工业技术—材料科学与工程]