摘要
通过高温拉伸试验研究了Ti2AlNb合金在温度为900~1000℃、应变速率为0.0001~0.01 s^（-1）下变形温度及应变速率对材料伸长率和抗拉强度的影响,并基于试验结果研究了材料应变速率敏感性指数随温度及应变速率的变化趋势。结果表明：Ti2AlNb合金应变速率敏感性指数随温度及应变速率的变化呈先升高后下降的趋势,在温度为975℃、应变速率为0.0005 s^（-1）条件下达到峰值,随后快速下降。通过扩展Rossard提出的粘塑性关系式,修正了基于Backoften方程所建立的应力-应变本构关系式,建立了材料在不同温度下的热变形本构方程。试验结果与模型计算结果基本吻合,可用于表征Ti2AlNb合金在高温下的热变形行为。
The effect of deformation temperature and strain rate on material elongation rate and strength of Ti2 AlNb alloy was investigated by high temperature tensile experiment at 900-1000 ℃ with strain rate 0. 0001-0. 01 s^（-1）,and the variation trend of the strain rate sensitivity index with temperature and strain rate was researched based on the experimental results. The results show that strain rate sensitivity index of Ti2 AlNb alloy increases first and then decreases with the change of temperature and strain rate,and reaches the peak at 975 ℃with strain rate of 0. 0005 s^（-1）,then decreases quickly. The strain-stress constitutive equation established based on the Backoften equation was modified and the thermal deformation constitutive equation under different temperatures was established by extending Rossard＇s viscoplastic relation. The calculated results are well matched with the experimental results,and can be used to characterize the thermel deformation behavior of Ti2 AlNb alloy under high temperature.
作者
张臣
齐飞
李永兵
周英丽
周永松
吴锋
ZHANG Chen;QI Fei;LI Yong-bing;ZHOU Ying-li;ZHOU Yong-song;WU Feng(State Key Laboratory of Advanced Forming Technology and Equipment, Advanced Manufacture Technology Center, China Academy of Machinery Science ＆ Technology, Beijing 100083, China;Jiangsu Institute, China Academy of Machinery Science ＆ Technology, Changzhou 213164, China;Changzhou Tiantai Aviation Materials Technology Co. , Ltd. , Changzhou 213000, China)
出处
《塑性工程学报》
CAS
CSCD
北大核心
2018年第1期212-217,共6页
Journal of Plasticity Engineering
基金
国家科技重大专项资助项目:高档数控机床与基础制造装备(2014ZX04001-141-04)
