摘要
以热轧态Ti80合金作为基材,在Gleeble-3500热模拟测试机上进行高温压缩测试,变形温度为800~1000℃,应变速率为0.01~10 s^(−1),总变形比例为75%。结果表明:Ti80钛合金在800~950℃时处于α+β两相区,其流变行为受变形温度和应变速率的显著影响。Ti80钛合金的加工硬化主要来自于初始α相中位错密度的提高,变形温度的提高会导致α相的减少,流变峰值应力不断降低,过高的应变速率会导致α相内位错运动受阻。Ti80钛合金中的初始α相更容易发生动态回复和动态再结晶,随着变形温度的提高,初始α相不断减少,动态软化程度逐渐减小直至接近0。为保证钛管热轧的稳定性,应适当提高变形温度,保证Ti80钛合金热变形组织具有较高的β相体积分数,同时避免应变速率过高造成轧制载荷过大。
Hot-rolled Ti80 alloy was used as the substrate,and the high temperature compression test was carried out on the Gleeble-3500 thermal simulation tester.The deformation temperature was 800~1000℃,the strain rate was 0.01~10 s^(−1),and the total deformation ratio was 75%.The results show that the phase of Ti80 titanium alloy was in theα+βtwo-phase region at 800~950℃,and its rheological behavior was significantly affected by the deformation temperature and strain rate.The work hardening of Ti80 titanium alloy mainly came from the increase of the dislocation density in the initialαphase.The increase of the deformation temperature led to the decrease of theαphase,and the rheological peak stress continued to decrease.And the excessively high strain rate restrained the movement of the dislocations in theαphase.The initialαphase in Ti80 titanium alloy was more prone to dynamic recovery and dynamic recrystallization.As the deformation temperature increased,the initialαphase continued to decrease,and the dynamic softening degree gradually decreased until it approached zero.In order to ensure the stability of the hot rolling of the titanium tube,the deformation temperature should be appropriately increased for obtaining a higherβphase volume fraction of the hot deformed structure in the Ti80 titanium alloy,and avoiding the excessive rolling load caused by the excessively high strain rate.
作者
付文
周晓锋
利成宁
程方杰
王东坡
Fu Wen;Zhou Xiaofeng;Li Chengning;Cheng Fangjie;Wang Dongpo(School of Materials Science and Engineering,Tianjin University,Tianjin 300350,China;Tianjin Pipe(Group)Corporation,Tianjin 300301,China;Tianjin Key Laboratory of Advanced Joining Technology,Tianjin 300350,China)
出处
《钢铁钒钛》
CAS
北大核心
2021年第6期78-83,共6页
Iron Steel Vanadium Titanium
基金
天津市科技计划项目(编号:18ZXJMTG00140)。
关键词
钛合金管
热轧
变形温度
应变速率
两相区
流变行为
titanium alloy tube
hot rolling
deformation temperature
strain rate
two-phase region
rheological behavior
