摘要
采用SEM和TEM对在高温中等应变速率包套轧制后的Ti-45Al-7Nb-0.3W(摩尔分数,%)合金显微组织进行了研究。结果表明:当轧制温度为1270℃,道次变形量为30%且总变形量达到83%时,板材未出现明显裂纹。中等应变速率下轧制板材中出现了大量变形孪晶,部分变形孪晶甚至穿越相邻晶粒进入下一个晶粒。变形后的合金组织晶界处发现大量弥散分布在晶界的β相,且发生了明显的动态再结晶。层片组织的变形机理主要为变形孪生与弯曲,在强弯曲区域发生了层片组织的球化,这种球化是动态再结晶的早期特征。Ti-45Al-7Nb-0.3W合金在中等应变速率轧制下的变形机制为孪生以及动态再结晶。
The microstructure of Ti-45Al-7Nb-0.3W(mole fraction,%)alloy after high temperature medium strain rate pack rolling was studied by SEM and TEM.The results show that when the rolling temperature is 1270℃,the pass reduction is 30%and the total deformation reaches 83%,no obvious crack appears in the plate.A large number of deformed twins appear in the microstructure of the medium strain rate rolling plate.Some deformation twins even pass through adjacent grains to enter the next grain.A large number ofβphases distributed at the grain boundaries are found,and significant dynamic recrystallization occurs.The deformation mechanism of lamellar structure is mainly deformed twinning and bending,the spheroidization of lamellar structure occurs in the strong bending region.The spheroidization of the lamella is the early characteristic of dynamic recrystallization.The deformation mechanism of Ti-45Al-7Nb-0.3W alloy at moderate strain rate rolling is twinning and dynamic recrystallization.
作者
陈成贵
梁霄鹏
李慧中
张强
CHEN Chenggui;LIANG Xiaopeng;LI Huizhong;ZHANG Qiang(School of Materials Science and Engineering,Central South University,Changsha 410083,China;State Key Laboratory of Powder Metallurgy,Central South University,Changsha 410083,China;Key Laboratory of Nonferrous Metal Materials Science and Engineering,Ministry of Education,Central South University,Changsha 410083,China)
出处
《热加工工艺》
北大核心
2023年第9期21-25,共5页
Hot Working Technology
基金
国家自然科学基金资助项目(51774335,52001334)
湖南省自然科学基金资助项目(2019JJ40374)。
