Ti55531合金热压缩模拟研究  

Study on the simulation of hot compressing for titanium alloy Ti55531

作　　者：李志燕[1] 郑为为[2] 沙爱学[1] 魏学业[2] 

机构地区：[1]北京航空材料研究院,北京100095 [2]北京科技大学新金属材料国家重点实验室,北京100083

出　　处：《锻压技术》2015年第6期121-125,共5页Forging & Stamping Technology

基　　金：航空科学基金资助项目(2012ZEL056)

摘　　要：在Gleeble-1500热模拟试验机上,当应变速率为0.001～10 s-1、变形温度为700～900℃时,采用高温压缩试验对Ti-55531钛合金热压缩变形中流变应力行为进行研究。研究结果表明,两相区变形时,曲线呈动态再结晶型,单相区变形时,曲线呈动态回复型。流变应力随着变形温度的升高而降低,随应变速率的提高而增大。采用双曲正弦模型确定该合金的变形激活能,两相区变形激活能为407.75 k J·mol-1,单相区变形的形变激活能为157.97 k J·mol-1,建立了两相区和单相区变形的本构方程。误差分析表明,流动应力计算值与试验值之间的相对误差小于10%,所建立的本构关系能比较精确地描述Ti-55531钛合金热加工过程中的流动行为。The flow stress behavior of titanium alloy Ti55531 during hot compression deformation was studied by high temperature com- pression test at the deformation temperature 700 -900 ℃and the strain rate 0. 001 - 10 s -1 on the Gleeble - 1500 press. The results show that the curve at （ α ＋ β） phase is of re-crystallization, while the curve at β phase is of dynamic recovery. The flow stress decreases with the increase of deformation temperature but increases with the increasing strain rate. Its deformation activation energy is determined by the Hyperbolic sine model, namely, 407.75 kJ · mol-1 on （α ＋ β） phase and 157.97 kJ · mol-l on β phase, and the constitutive equations at （ α ＋ β） phase were β phase are established. The results of error analysis show that the relative error between the calculated and ex- perimental values of flow stress is less than 10%. Thus, the constitutive equation can be used to describe the flow behavior of titanium al- loy Ti55531 in the hot- working process.

关 键 词：Ti55531钛合金 热压缩 应力 激活能 

分 类 号：TG146.23[一般工业技术—材料科学与工程]