压铸态Al-Zn-Mg-Cu合金的等温压缩变形及组织演变行为  

Isothermal compression deformation and microstructure evolution behavior of die cast Al-Zn-Mg-Cu alloy

作　　者：赵晓东[1] 张奇柱 杨晓辉 楚志兵[1] 李亚杰[1] 秦凤明 Zhao Xiaodong;Zhang Qizhu;Yang Xiaohui;Chu Zhibing;Li Yajie;Qin Fengming(School of Materials Science and Engineering,Taiyuan University of Science and Technology,Taiyuan 030024,China)

机构地区：[1]太原科技大学材料科学与工程学院,山西太原030024

出　　处：《锻压技术》2022年第7期235-242,共8页Forging & Stamping Technology

基　　金：山西省重点研发计划项目(201903D121040)。

摘　　要：采用Gleeble-3800热模拟试验机,在变形温度为250~450℃、应变速率为0.001~1 s^(-1)的条件下对压铸态Al-Zn-Mg-Cu合金进行等温压缩试验,研究该合金的热变形行为和组织演变规律。通过相关参数线性拟合建立了该合金的Arrhenius双曲正弦本构方程,其应力指数和热变形激活能分别为8.098和359.28 kJ·mol^(-1)。微观组织分析结果表明,该合金的热变形行为对变形温度和应变速率较为敏感,lnZ值较低的变形条件有利于动态再结晶发生。结合EBSD分析结果发现,该合金在较高lnZ值的变形条件下以动态回复为主要软化机制,而低lnZ值的变形条件下受动态回复和连续动态再结晶的共同作用,主要形核方式为弓出机制。The isothermal compression test of die cast Al-Zn-Mg-Cu alloy was conducted under the conditions of the deformation temperature of 250-450℃and the strain rate of 0.001-1 s^(-1) by thermal simulated test machine Gleeble-3800,and the hot deformation behavior and microstructure evolution law of the alloy were studied.Then,the Arrhenius hyperbolic sinusoidal constitutive equation of the alloy was established by linear fitting of relevant parameters,and the stress index and thermal deformation activation energy were 8.098 and 359.28 kJ·mol^(-1),respectively.The results of microstructure analysis show that the hot deformation behavior of the alloy is sensitive to deformation temperature and strain rate,and the deformation condition with low lnZ value is conducive to dynamic recrystallization.Combined with the results of EBSD analysis,it is found that the dynamic recovery is the main softening mechanism under the deformation condition of high lnZ value for the alloy,while under the deformation condition of low lnZ value,due to the combined action of dynamic recovery and continuous dynamic recrystallization,its main nucleation mode is bow-out mechanism.

关 键 词：AL-ZN-MG-CU合金 等温压缩 本构模型 组织演变 再结晶 

分 类 号：TG146.2[一般工业技术—材料科学与工程]