Dynamic recrystallization and silicide precipitation behavior of titanium matrix composites under different strains  

不同应变下钛基复合材料的动态再结晶和硅化物析出行为

作　　者：Er-tuan ZHAO Shi-chen SUN Jin-rui YU Yu-kun AN Wen-zhen CHEN Rui-run CHEN 赵而团;孙世臣;于金瑞;安钰坤;陈文振;陈瑞润(山东理工大学机械工程学院,淄博255022;哈尔滨工业大学材料科学与工程学院,威海264209;哈尔滨工业大学金属精密热加工国家重点实验室,哈尔滨150001)

机构地区：[1]School of Mechanical Engineering,Shandong University of Technology,Zibo 255022,China [2]School of Materials Science and Engineering,Harbin Institute of Technology,Weihai 264209,China [3]National Key Laboratory for Precision Hot Processing of Metals,Harbin Institute of Technology,Harbin 150001,China

出　　处：《Transactions of Nonferrous Metals Society of China》2021年第11期3416-3427,共12页中国有色金属学报（英文版）

基　　金：financial supports from the National Natural Science Foundation of China (No. 51871184);the Natural Science Foundation of Shandong Province, China (No. ZR2019MEM037);the Zhoucun School-City Integration Development Plan, China (No. 2020ZCXCZH03);the School-city Integration Development Project of Zibo, China (No. 2019ZBXC022)。

摘　　要：In order to elucidate the microstructure evolution and silicide precipitation behavior during high-temperature deformation,TiB reinforced titanium matrix composites were subjected to isothermal hot compression at 950℃,strain rate of 0.05 s^(−1) and employing different strains of 0.04,0.40,0.70 and 1.00.The results show that with the increase of strain,a decrease in the content,dynamic recrystallization of theαphase and the vertical distribution of TiB along the compression axis lead to stress stability.Meantime,continuous dynamic recrystallization reduces the orientation difference of the primaryαphase,which weakens the texture strength of the matrix.The recrystallization mechanisms are strain-induced grain boundary migration and particle stimulated nucleation by TiB.The silicide of Ti_(6)Si_(3) is mainly distributed at the interface of TiB andαphase.The precipitation of silicide is affected by element diffusion,and TiB whisker accelerates the precipitation behavior of silicide by hindering the movement of dislocations and providing nucleation particles.为了研究TiB增强钛基复合材料在高温变形过程中的组织演变和硅化物析出行为,950℃时在应变速率为0.05 s~(-1),应变分别为0.04、0.40、0.70和1.00的工况下对其进行等温热压缩试验。研究发现:随着应变的增加,初生α相含量降低及其发生的连续动态再结晶和TiB增强相沿垂直压缩轴方向的定向分布导致应力趋于稳定,同时连续动态再结晶导致初生α相的取向差减小,从而削弱基体的织构强度。动态再结晶的机制主要是应变诱导晶界迁移以及TiB增强相诱导晶粒形核。元素扩散促进硅化物的析出,析出的Ti_(6)Si_(3)型硅化物主要分布在Ti B及α相的界面上,TiB增强相通过阻碍位错的运动和提供形核质点加速硅化物的析出行为。

关 键 词：titanium matrix composites dynamic recrystallization silicide precipitation hot compression 

分 类 号：TB333[一般工业技术—材料科学与工程]