Ti-2%Al-2.5%Zr钛合金的高温持久强度  

High Temperature Creep Rupture Strength Study of Ti-2%Al-2.5%Zr Titanium Alloy

作　　者：李远睿[1] 胡跃均[1] 王书珍[1] 

机构地区：[1]重庆大学材料科学与工程学院,重庆400030

出　　处：《重庆大学学报（自然科学版）》2007年第3期56-59,共4页Journal of Chongqing University

基　　金：核燃料及材料国家重点实验室基金资助项目(99JS85.6.1.JW.2004)

摘　　要：介绍了Ti-2%Al-2.5%Zr钛合金的成分、组织后,首先测定出了该合金在350℃下的σb和σ0.2值.根据试验的特点、试材的组织状况及约比温度等因素确定了试验采用的6个应力水平点.按GB6395-86《金属高温拉伸持久试验方法》标准规定对该合金进行了350℃下的持久强度试验.对获得的数据用最小二乘法进行回归处理后,得到了适用于工作应力在σ30.502℃<σ<σb350℃范围的方程;而适用于工作应力σ<σ03.502℃并可以外推一个数量级的方程最后,观察到试验后该种钛合金的金相组织发生了明显的变化:在集中塑性变形区呈明显的纤维状,而在均匀塑性变形区则由于回复再结晶而变成细小的等轴晶了.After introducing the composition and microstructure of Ti -2% Al -2.5% Zr titanium alloy, σb and σ0.2of this alloy are measured at 350 ℃. And determine 6 stress level points according as test character, microstructure of test material and temperature. Then, the creep rupture strength experiment at high temperature of 350 ℃ is carried out according to the GB6395 - 86 Metallic Materials Stress Rupture Testing at elevated temperature. The data of the test result are processed and the regressive equations are obtained： σ = 416.18 -0.030 4t, work stress is between σ0.2^350and σb^350 ; Furthermore, σ 〈 σ0.2^350 equations derivated one order of magnitude is σ = 664.01t^-0.079. Finally, microstructure of the titanium alloy are changed markedly after test, it shapes fibrous structure in intensive plastic deformation zone, and forms small equiaxed grain owing to returning recrystallization in homogeneous plastic deformation zone.

关 键 词：钛合金 高温 持久强度 

分 类 号：TG111.8[金属学及工艺—物理冶金]