扩散连接TC4钛合金热变形特性及建模  

Hot deformation characteristics and modeling of diffusion bonding TC4 titanium alloy

作　　者：蔡钟满 陈家瑞 李勇[1] 李晓星[1] Cai Zhongman;Chen Jiarui;Li Yong;Li Xiaoxing(School of Mechanical Engineering&Automation,Beihang University,Beijing 100191,China)

机构地区：[1]北京航空航天大学机械工程及自动化学院,北京100191

出　　处：《锻压技术》2024年第7期264-272,共9页Forging & Stamping Technology

基　　金：国家自然科学基金资助项目(52005020);中央高校基本科研业务基金(YWF-23-L-1012)。

摘　　要：在变形温度为750~850℃、应变速率为0.0001~0.1 s^(-1)条件下,对扩散连接TC4钛合金试样进行热拉伸试验,获取了应力-应变曲线,研究了扩散连接TC4钛合金试样的热拉伸变形行为及其机理。此外,建立了面向扩散连接TC4钛合金的基于内变量的统一本构模型,该模型能够描述扩散连接TC4钛合金相变、位错密度、再结晶行为和损伤等内部变量与应力之间的关系。基于试验结果,通过遗传算法对模型参数进行了标定,该模型可用于扩散连接钛合金的多温度多应变速率下的热成形行为预测,为精确模拟扩散连接钛合金热成形提供了理论与模型依据。The hot tensile tests of diffusion bonding(DB)TC4 titanium alloy specimen were carried out at the deformation temperature of 750-850℃and the strain rate of 0.0001-0.1 s^(-1),and the stress-strain curves were obtained to research the hot tensile deformation behaviour and mechanism of diffusion bonding TC4 titanium alloy specimen.Then,an unified constitutive model based on internal variables for diffusion bonding TC4 titanium alloy was established,which described the relationship between internal variables such as phase transformation,dislocation density,recrystallization behaviour,and damage and stress in diffusion bonding TC4 titanium alloy.Based on the test data,the model parameters were calibrated by genetic algorithm(GA),which could predict the hot deformation behaviour of diffusion bonding titanium alloys at multiple temperatures and strain rates and provide a theoretical basis and model for accurately simulating the hot forming of diffusion bonding titanium alloys.

关 键 词：TC4钛合金 扩散连接 热变形 本构模型 内部变量 

分 类 号：TG146.23[一般工业技术—材料科学与工程]