Cu-Ag合金高温流变特性及其改进的本构模型  

High Temperature Deformation Properties and Modification of Constitutive Model of Cu-Ag Alloy

作　　者：王梦寒[1] 孟烈[1] 危康 岳宗敏[1] 汪丰林 

机构地区：[1]重庆大学,重庆400044 [2]Institute for Materials Research,Tohoku University

出　　处：《稀有金属材料与工程》2017年第12期3733-3738,共6页Rare Metal Materials and Engineering

基　　金：中央高校基本科研业务费资助项目(CDJZR14130006)

摘　　要：在变形温度为973~1123 K和应变速率0.01~10 s^(-1)条件下对Cu-6%Ag(质量分数)合金进行等温热压缩试验。利用试验所得流变应力-应变曲线,分析了高应变速率下Cu-6%Ag合金高温塑性变形时微观组织的演变行为;研究了高温塑性变形中材料的变形机制;构建了一种简化的本构模型,并引入Arrhenius方程及Z参数对模型进行改进。结果表明:Cu-6%Ag合金在热塑性变形过程中发生了明显的动态回复和动态再结晶;在应变速率为0.1、1及10 s-1,温度为1123 K的变形条件下发生孪生,造成流变应力突变而升高,出现应力谷值;经改进后的本构模型,考虑了应变、变形温度及变形速率对流变特性的影响,预测精度较高,更利于通过计算机语言写入有限元软件进行分析计算。The hot deformation behavior of Cu-6%Ag（mass fraction） alloy was described by hot compression tests in the temperature range of 973-1123 K and stain rates of 0.01-10 s^-1.The microstructure evolution of the alloy was investigated.The true stress-strain curves were studied to reveal the hot deformation mechanism of Cu-6% Ag alloy.A simple constitutive model was established.The Arrhenius equation and Z were quoted to modify the model.The results show that the dynamic recovery and dynamic recrystallization occur in Cu-6% Ag alloy during hot deformation.And twinning behavior is observed at the strain rates of 0.1,1 and 10 s^-1 and the temperature of 1123 K.This twining behavior results in sharp changing of flow stress.With the increase of flow stress,a valley of stress is observed directly.The modified model which integrates the influence of temperature,strain rate and strain on flow characteristic could predict the stress accurately and be compiled easily.

关 键 词：Cu-6%Ag合金 高温塑性变形 微观组织 孪生 本构模型 

分 类 号：TG146.11[一般工业技术—材料科学与工程]