铝锶合金高温塑性变形行为及本构方程  

Pyroplastic deformation behavior and constitutive equation of Al-Sr alloy

作　　者：万帆 运新兵[1] 毕胜[1] 裴久杨[1] WAN Fan;YUN Xin-bing;BI Sheng;PEI Jiu-yang(Engineering Research Center of Continuous Extrusion, Dalian Jiaotong University, Dalian 116028, China)

机构地区：[1]大连交通大学连续挤压工程研究中心,大连116028

出　　处：《中国有色金属学报》2018年第5期888-896,共9页The Chinese Journal of Nonferrous Metals

基　　金：辽宁省高等学校优秀人才支持计划资助项目(LR2015011)~~

摘　　要：采用Gleeble-1500型热模拟试验机进行高温压缩实验,结合连续挤压工艺制定热压缩实验方案,研究铝锶合金高温塑性变形行为,分析变形温度、应变速率对铝锶合金热变形过程中流变应力和Al_4Sr相形态的影响,并采用线性回归的方法建立铝锶合金高温下的本构方程。结果表明:铝锶合金的热塑性变形软化机制以动态回复为主;在热变形过程中流变应力随变形温度的升高而减小,随应变速率的增大而增大;变形温度为400℃时Al_4Sr相破裂严重,而当温度为500℃时Al_4Sr相具有韧性而易于弯曲;可用包含Zener-Hollomon参数的Arrhenius双曲正弦模型描述其热变形行为。The pyroplastic deformation experiment of Al-Sr alloy was studied on the Gleeble-1500 thermal-mechanical simulator, which was based on the continuous extrusion process. The pyroplastic deformation behavior of Al-Sr alloy was systematically studied the effects of deformation temperature and strain rate on the flow stress and Al4Sr phase of Al-Sr alloy during hot deformation were analyzed, and the constitutive equation of Al-Sr alloy by linear regression analysis was established. The results show that the main softening mechanism of the Al-Sr alloy under the pyroplastic deformation is dynamic recovery; and the rheological stress decreases with increasing the temperature, and increases with increasing the strain rate. When the deformation temperature was 400 ℃, the Al4Sr phase break seriously; once the deformation temperature was 500 ℃, the particles become ductile and flexible. The thermal deformation behavior can be described by the Arrhenius hyperbolic sine equation with Zener-Hollomon parameters.

关 键 词：铝锶合金 高温塑性变形 流变应力 显微组织 本构方程 

分 类 号：TG301[金属学及工艺—金属压力加工] TG146.2[一般工业技术—材料科学与工程]