β-T51Z合金的热变形行为与组织演变研究  

Hot Deformation Behavior and Microstructure Evolution ofβ-T51Z Alloy

作　　者：毛敏[1] 栾佰峰[1] 李飞涛 廖仲尼 邱日盛[1] Mao Min;Luan Baifeng;Li Feitao;Liao Zhongni;Qiu Risheng(Chongqing Key Laboratory for Light Metals,International Joint Laboratory for Light Alloys Ministry of Education,Chongqing University,Chongqing 400044,China)

机构地区：[1]重庆大学教育部轻合金材料国际联合实验室轻金属科学与技术重庆市重点实验室,重庆400044

出　　处：《稀有金属材料与工程》2020年第4期1211-1219,共9页Rare Metal Materials and Engineering

基　　金：国家自然科学基金(51531005,51571174,51421001);中央高校基本科研业务费(106112017CDJQ138803)。

摘　　要：针对亚稳β-T51Z(51.1Zr-40.2Ti-4.5Al-4.2V)合金,采用Gleeble-3500试验机进行热模拟实验,利用EBSD和TEM分析了变形温度和应变速率对合金热变形行为的影响及其组织演变规律。结果表明:T51Z合金在热变形时,其流变应力曲线呈现典型的单峰动态再结晶特征,其应力增幅随着变形温度的降低或应变速率的增加逐渐增加。基于峰值应力建立了合金热变形本构方程,计算得出热变形激活能为159.57kJ/mol,该合金在热压缩过程中的变形机制主要与位错的交滑移有关。变形温度和应变速率对合金形变组织影响较大,整个热变形过程都存在动态回复,随着变形温度的升高或应变速率的降低,合金动态再结晶分数逐渐增大。在800℃/10 s^-1变形条件下,合金容易形成绝热剪切带,宏/微观变形不均匀现象严重。The hot deformation behavior and microstructure evolution of metastableβ-T51Z(51.1Zr-40.2Ti-4.5Al-4.2V)alloy at different deformation temperatures and strain rates were studied using Gleeble 3500.EBSD and TEM results show that the compressing curves in hot deformation have a typical characteristic of single-peak dynamic recrystallization,and the stress amplification increases gradually with the decrease of deformation temperatures or the increase of strain rates.Based on the peak stress,the constitutive equation of thermal deformation of alloy was established,and the activation energy Q is 159.57 kJ/mol.The deformation mechanism of alloy during hot compression is mainly related to the cross slip of dislocation.The deformation temperature and strain rate have a great influence on the deformation microstructure.Dynamic recovery exists throughout the whole hot deformation process.With the increase of deformation temperatures or the decrease of strain rates,the fractions of dynamic recrystallization increase gradually.When the deformation temperature is 800℃and strain rate is 10 s^-1,the adiabatic shear band is easily formed,and the macro/micro deformation is not uniform.

关 键 词：β-T51Z合金 热模拟 本构方程 形变组织 位错滑移 动态再结晶 

分 类 号：TG146.414[一般工业技术—材料科学与工程]