TA32钛合金应力松弛行为及热成形回弹预测  

Stress Relaxation Behavior and Hot Forming Springback Prediction of TA32 Titanium Alloy

作　　者：杨丰 慕延宏 杜立华 YANG Feng;MU Yanhong;DU Lihua(Metal Forming Technology Research Institute,AVIC Manufacturing Technology Institute,Beijing 100024,China;Aeronautical Key Laboratory for Plastic Forming Technologies,AVIC Manufacturing Technology Institute,Beijing 100024,China)

机构地区：[1]中国航空制造技术研究院金属成形技术研究所,北京100024 [2]中国航空制造技术研究院塑性成形技术航空科技重点实验室,北京100024

出　　处：《航空制造技术》2025年第5期114-120,126,共8页Aeronautical Manufacturing Technology

基　　金：航空科学基金(20200036025002)。

摘　　要：TA32钛合金相比TC4钛合金具有更为优异的高温抗蠕变性能,在高声速飞行器中具有广泛应用前景。TA32钛合金复杂构件热成形后存在一定的回弹现象,无法满足零件高精度制造的要求。研究了TA32钛合金在不同温度(650 ℃、700℃、750 ℃、800℃)和预应变(2%、4%、8%)条件下的应力松弛行为,发现温度越高,第一阶段应力松弛速率越快,且应力松弛极限越低。基于试验数据,拟合了五次延迟函数的应力松弛显示本构方程,进一步建立了Arrhenius型蠕变本构模型。建立了考虑高温应力松弛效应的TA32钛合金加强框热成形仿真模型,并通过热成形试验和回弹测试验证了仿真模型的可靠性。模拟结果表明,保压能有效降低零件回弹,保压时间由10 s增加到1800 s,回弹量由3.15 mm减小到2.55 mm。加强框零件在保压300 s后,已达应力松弛极限,回弹几乎不再发生变化。TA32 titanium alloy has better creep resistance than TC4 titanium alloy at high-temperatures,which is widely applied in the hypersonic aircraft.It is challenging to meet the dimensional requirements for the complex components of TA32 titanium alloy due to the springback after hot forming.The stress relaxation behavior of TA32 titanium alloy was studied at different temperatures(650 ℃,700 ℃,750 ℃,800 ℃) and pre-strains(2%,4%,8%).With the increasing temperature,the stress relaxation rate at the first stage increases,and the limit of stress relaxation decreases.Based on the experimental data,the explicit constitutive equation of stress relaxation was fitted with the quintic delay function,and the Arrhenius type creep constitutive model was established.Considering the effect of high-temperature stress relaxation,the hot forming simulation model of a TA32 titanium alloy reinforced frame was established,and hot forming and springback test verified the reliability of the simulation model.The results show that the springback can be effectively reduced due to holding process.With the holding time increasing from 10 s to 1800 s,the springback decreases from 3.15 mm to 2.55 mm.When the holding time reaches 300 s,the stress reaches to the relaxation limit,and the springback is almost unchanged.

关 键 词：应力松弛 TA32钛合金 热成形 回弹 数值模拟 

分 类 号：TG3[金属学及工艺—金属压力加工]