Al-Cu-Mg-Ag合金热变形本构方程模型  

Constitutive Equation Model for Hot Deformation of Al-Cu-Mg-Ag Alloy

作　　者：李慧中[1] 李洲[1] 郭菲菲[1] 孟力平[1] 梁霄鹏[1] 

机构地区：[1]中南大学材料科学与工程学院、有色金属材料科学与工程教育部重点实验室

出　　处：《特种铸造及有色合金》2008年第11期823-826,共4页Special Casting & Nonferrous Alloys

基　　金：国家重点基础研究发展规划(973计划)资助项目(2005CB623706);中国博士后基金资助项目(20070420828);中南大学博士后基金资助项目(2008-8)

摘　　要：在Gleeble-1500热模拟机上进行高温等温压缩试验,研究了Al-Cu-Mg-Ag合金在变形温度为300～500℃、应变速率为0.01～10.00s-1条件下的流变变形行为,建立了Al-Cu-Mg-Ag合金热变形本构方程。结果表明,流变应力随温度的降低、应变速率的提高而增大,在应变速率小于10.00s-1的条件下,流变应力随应变增加而迅速增大,达到峰值后趋于平稳,表现出动态回复的特征;在应变速率为10.00s-1,温度大于300℃的条件下,应力达到峰值后逐渐下降,并出现锯齿波动现象,表明合金发生了局部动态再结晶;Al-Cu-Mg-Ag合金高温变形时的流变行为可用Zener-Hollomon参数来描述,其变形激活能为160.08kJ/mol。The flow stress behavior of Al-Cu-Mg-Ag alloy was tested with Gleeble-1500 machine by isothermal compression at 300～500℃ and strain rate at 0.01～10 s-1,and a constitutive equation model for hot deformation of the alloy was established.The results reveal that the flow stress is increased with decreasing in temperature and increasing in strain rate.The flow stress of the alloy is sharply increased to peak value and then tends towards a constant with raising in strain rate in case of strain rate less than 10 s-1,showing dynamic recovery,while it reaches the peak value and then decreases with the occurrence of saw-tooth fluctuation in case of strain rate of 10s-1 and deformation temperature more than 300 ℃,exhibiting partial dynamic recrystallization.The flow stress of Al-Cu-Mg-Ag alloy during high temperature deformation can be expressed by the Zener-Hollomon parameters in the hyperbolic sine function,and deformed activation energy of the alloy makes 160.08 kJ/mol.

关 键 词：Al-Cu—Mg—Ag合金 热变形 流变应力 本构方程 

分 类 号：TG146.21[一般工业技术—材料科学与工程]