Al-1.03Mg-1.00Si-0.04Cu铝合金热压缩变形及其加工图

党小荔^{1, 2}，杨伏良^{1, 2}

(1. 中南大学 材料科学与工程学院，湖南 长沙，410083；
2. 中南大学 有色金属材料科学与工程教育部重点实验室，湖南 长沙，410083)

摘 要：采用Gleeble-1500热压缩模拟试验机在变形温度310~510 ℃、应变速率0.001~10 s^-1的条件下对Al-1.03Mg-1.00Si-0.04Cu铝合金进行热压缩实验，研究该合金热变形行为及热加工特征，建立该合金热变形时的本构方程和加工图。研究结果表明：Al-1.03Mg-1.00Si-0.04Cu铝合金热变形过程中，随着应变速率的增加和变形温度的降低，流变应力上升，合金流变应力达到峰值后曲线呈现稳态流变特征；合金变形激活能Q平均值为170.878 kJ/mol，高温变形行为可用双曲正弦形式的本构方程来描述；根据动态材料模型建立合金的加工图，在320~400 ℃和0.001~0.005 s^-1范围内变形时加工图上出现一个动态回复的峰区，峰值效率为27%；Al-1.03Mg-1.00Si-0.04Cu铝合金高温变形时，Mg₂Si相的析出有效阻碍了位错运动，合金峰区下变形激活能大于多晶纯铝的激活能。

关键词：铝合金；热变形；动力学分析；加工图

Hot compression deformation and processing maps of Al-1.03Mg-1.00Si-0.04Cu aluminum alloy

DANG Xiao-li^{1, 2}, YANG Fu-liang^{1, 2}

(1. School of Materials Science and Engineering, Central South University, Changsha 410083, China;
2. Key Laboratory of Nonferrous Metal Materials Science and Engineering, Ministry of Education,
Central South University, Changsha 410083. China)

Abstract:Hot-compression tests of Al-1.03Mg-1.00Si-0.04Cu aluminum alloy were carried out at 310-510 ℃ and strain rates of 0.001-10 s^-1 on a hot-simulation machine Gleeble-1500.The deformation behavior and hot work-ability of the alloy were studied and the constitutive equation and processing map were established on the basis of experiment. The results show that the flow stress of Al-1.03Mg-1.00Si-0.04Cu aluminum alloy for hot deformation increases with the increase of strain rate and decrease of deformation temperature, and exhibits steady state flow behavior when the flow stress reaches the peak value. The hot deformation behavior of Al-1.03Mg-1.00Si-0.04Cu aluminum alloy can be described by the hyperbolic sine constitutive equation，and an activation energy of 170.878 kJ/mol. According to the processing map created based on the dynamic materials model, the dynamic recovery of the alloy mainly occurs in a region at temperature of 320-400 ℃ and stain rates of 0.001-0.005 s^-1, with a peak efficiency of 27%. During the hot deformation of Al-1.03Mg-1.00Si-0.04Cu aluminum alloy, Mg₂Si phase can effectively hinder dislocation motion, and the deformation activation energy of the peak district is lager than polycrystalline pure aluminum.

Key words:aluminum alloy; hot deformation; kinetic analysis; processing map