2A70铝合金热变形应力行为研究  

Study on Flow Stress of 2A70 Aluminum Alloy under Hot Deformation

作　　者：张所全[1] 汪凌云[1] 黄光胜[1] 黄光杰[1] 牛禧[1] 

机构地区：[1]重庆大学材料科学与工程学院,重庆400044

出　　处：《轻合金加工技术》2005年第10期46-49,共4页Light Alloy Fabrication Technology

摘　　要：在Gleeble-1500热模拟机上,对2A70铝合金进行等温热压缩试验,变形温度为300℃～500℃,应变速率为0.01 s-1～10 s-1,研究其热压缩变形的流变应力行为.结果表明:2A70铝合金真应力-应变曲线中,流变应力开始随应变增加而增大,达到峰值后趋于平稳,表现出动态回复特征;在应变速率ε=1.0 s-1,变形温度高于420℃条件下,应力出现锯齿波动,表现出不连续动态再结晶特征.在用本构方程描述2A70铝合金热变形行为时,其变形激活能Q为180.83 kJ/mol.The flow stress behavior of 2A70 aluminum alloy during hot deformation conditions was studied by isothermal hot com- pression on Gleeble-1500.The deformation temperature range from 300℃ to 500℃ and the strain rate range from 0.01 s^-1 to 10 s^-1 . The experimental results indicated that the flow stress of 2A70 aluminum alloy increases with increasing strain and tends to be constant after a peak value showing dynamic recover; when the strain rate is 1.0 s^-1 and the deformation temperature is more than 420℃, the flow stress saw tooth fluctuates, showing discontinuous dynamic recrystallization.The deformation activation energy of 2A70 aluminum alloy is 180.83 kJ/mol from constitutive equation.

关 键 词：2A70铝合金 高温变形 流变应力 激活能 

分 类 号：TG115.5[金属学及工艺—物理冶金]