摘要
采用扫描电子显微镜(SEM)/电子背散射衍射(EBSD)、透射电子显微镜(TEM)等技术,研究经二步等温锻造得到的Ti-44Al-4Nb-1.5Cr-0.5Mo-0.1B-0.1Y(原子分数)合金单向高温压缩变形行为,揭示该合金变形过程中的组织演变及其变形机理。研究结果表明,该合金中的α2相在等温锻造及随后的单向高温压缩过程中大部分转变为B2相和γ相;高温变形过程中γ相主要细化机理为动态再结晶,而B2相则为动态回复;孪生及其交互作用是重要的变形机理,孪晶界促进了非连续动态再结晶,从而有助于细化晶粒。
Microstructural evolution and deformation mechanism of a two-step isothermally forged Ti-44Al-4Nb-1.5Cr-0.5Mo-0.1B-0.1Y(at.%)alloy were investigated during high temperature uniaxial compression,by using scanning electron microscopy(SEM)/electron backscattered diffraction(EBSD),and transmission electron microscopy(TEM).The results show that the most of theα2 phases transform into B2 andγphases after isothermal forging(ISF)and uniaxial high temperature compression.Dynamic recrystallization is the main refinement mechanism ofγphase,while B2 phase is dominated by dynamic recovery.Deformation twinning and twining interaction play an important role in the deformation mechanism of TiAl-based alloys and promote discontinuous dynamic recrystallization,hence lead to the refinement of microstructure.
作者
陶国强
祁广源
曲寿江
沈军
Tao Guoqiang;Qi Guangyuan;Qu Shoujiang;Shen Jun(Tongji University,Shanghai 201804,China;Dalian Power Supply Company,Dalian 116000,China)
出处
《钛工业进展》
CAS
北大核心
2018年第3期11-15,共5页
Titanium Industry Progress
基金
国家自然科学基金联合重点基金项目(U1302275)
国家自然科学基金青年科学基金项目(51305304)
国家科技重大专项课题资助项目(2013ZX04011061)
关键词
TIAL基合金
等温锻造
动态再结晶
孪生
TiAl-based alloy
isothermal forging
dynamic recrystallization
twinning
