预应变对TC4ELI钛合金变形行为的影响  

Influence of Pre-strain on Deformation Behavior of TC4ELI Titanium Alloy

作　　者：尹艳超 张帅锋 许亚利 蒋鹏 余巍 吕逸帆 YIN Yanchao;ZHANG Shuaifeng;XU Yali;JIANG Peng;YU Wei;LÜYifan(Luoyang Ship Material Research Institute,Luoyang 471023,China)

机构地区：[1]中国船舶集团有限公司第七二五研究所,河南洛阳471023

出　　处：《材料开发与应用》2023年第1期66-72,共7页Development and Application of Materials

摘　　要：对TC4ELI钛合金分别进行正向拉伸-反向压缩和正向压缩-反向拉伸试验,研究预应变对其后续反向变形行为的影响。结果表明:两种加载方式下,TC4ELI钛合金反向屈服强度均随着预应变的增大先降低后趋于稳定,表现出明显的包申格效应。预拉伸试验下的饱和预应变约为2%,预压缩试验下的饱和预应变约为4%。预压缩后强度降低更加明显。晶体取向差异和α相的高度不对称密排六方结构导致材料在加载过程中出现非均匀塑性变形,产生残余应力,这是诱发TC4ELI钛合金产生包申格效应的主要机制。Tension-unloading-compression and compression-unloading-tension tests are carried out to study the influence of pre-strain on the deformation behavior of TC4ELI titanium alloy.The results show that TC4ELI titanium alloy exhibits obvious bauschinger effect in both the tensile-first and compressive-first tests.With the increasing of pre-strain,the reverse yield strength decreases first and then tends to be stable.The saturated pre-strain under pre-tension test is about 2%,and the saturated pre-strain under pre-compressive test is about 4%.The reduction of yield strength is more obvious after pre-compression.The non-uniform plastic deformation due to the crystal orientation differences and highly asymmetric close hexagonal structure ofαphase contributes to the residual stress,which is the main cause for the bauschinger effect in TC4ELI titanium alloy.

关 键 词：TC4ELI钛合金 预拉伸 预压缩 包申格效应 

分 类 号：TG146.23[一般工业技术—材料科学与工程]