铸造技术2025，Vol.46Issue(9)：841-854,14.DOI:10.16410/j.issn1000-8365.2025.5134
Ti150钛合金热变形行为及显微组织演变研究
Study on the Hot-deformation Behavior and Microstructure Evolution of Ti150 Alloy
摘要
Abstract
The hot deformation behavior and microstructure evolution of a Ti150 near-α titanium alloy were investigated at deformation temperatures ranging from 970～1 040 ℃,strain rates ranging from 10-3～1 s-1,and a deformation amount of 60％.The influences of the true strain,deformation temperature,and strain rate on the flow stress were analysed.On the basis of the stress-strain curve data,an Arrhenius constitutive equation considering strain compensation was established,and a hot working map based on the Prasad criterion and criterion was constructed.The results show that the response of the flow stress to the strain rate of the Ti150 alloy varies significantly across different temperature ranges.The higher the deformation temperature is,the more sensitive the peak stress drop is to the deformation rate at higher strains.Discontinuous yielding is observed at high strain rates.The calculated activation energy for deformation is 919 kJ·mol-1.The prediction error of the established Arrhenius constitutive model considering strain compensation is AARE=6.53％,and the correlation coefficient R is 0.985 6,indicating high prediction accuracy.The hot working map indicates that the optimal process parameter range is a temperature range of 970 to 1 010 ℃ and a strain rate of 10-2 to 1 s-1.The microstructure characteristics of the samples were analysed via optical microscopy(OM)and electron backscatter diffraction(EBSD).The results show that the strain rate plays a decisive role in the microstructure evolution path.At high strain rates,intense plastic deformation leads to rapid dislocation proliferation,and deformation energy storage becomes the core factor driving phase transformation.However,owing to insufficient thermal activation time,microstructure reconstruction is limited.At low strain rates,sufficient thermal activation conditions promote the diffusion mechanism to dominate the phase transformation process,and dislocations gradually release distortion energy through dynamic recovery/recrystallization,ultimately achieving microstructure stabilization.关键词
Ti150/热模拟压缩实验/本构方程/热加工图/热变形行为Key words
Ti150/hot compression test/constitutive equation/hot processing map/hot deformation behavior分类
矿业与冶金引用本文复制引用
景春红,李江,邓浩,杨靖雲,傅强,彭文雅,李钢..Ti150钛合金热变形行为及显微组织演变研究[J].铸造技术,2025,46(9):841-854,14.基金项目
国家自然科学基金(52074231,52274396) （52074231,52274396）
