Influence of primary α-phase volume fraction on the mechanical properties of Ti-6Al-4V alloy at different strain rates and temperatures
Bimodal microstructures with primary α-phase volume fractions ranging from 14.3%to 57.1%were gained in Ti-6Al-4V(Ti-64)alloy through annealed in two-phase region at various temperatures below the β-transus point.Then the influence of the primary α-phase volume fraction on the mechanical properties of Ti-64 were studied.The results show that,at room temperature and a strain rate of 10?3 s?1,the yield stress decreases but the fracture strain augments with added primary α-phase volume fraction.The equiaxed primary α-phase possesses stronger ability to coordinate plastic deformation,leading to the improvement of the ductile as well as degradation of the strength of Ti-64 with higher primary α-phase volume fraction.As the temperature goes up to 473 K,the quasi-static yield stress and ultimate strength decrease first and then increase with the incremental primary α-phase volume fraction,due to the interaction between the work hardening and the softening caused by the DRX and the growth of the primary α-phase.At room temperature and a strain rate of 3×103 s?1,the varying pattern of strength with the primary α-phase volume fraction resembles that at a quasi-static strain rate.However,the flow stress significantly increases but the strain-hardening rate decreases compared to those at quasi-static strain rate due to the competition between the strain rate hardening and the thermal softening during dynamic compression process.
Yu Ren Shimeng Zhou Wenbo Luo Zhiyong Xue Yajing Zhang
School of energy,power and mechanical engineering,North China Electric Power University,Beijing 1022 No.52 Institute of China Ordnance Industries,Yantai,Shangdong 264003,China School of Materials Science and Engineering,University of Science and Technology Beijing,Beijing 100
国际会议
上海
英文
1-7
2017-12-28（万方平台首次上网日期，不代表论文的发表时间）