摘要
采用等温压缩试验法,研究了新型含Zr超高强Al-Zn-Mg-Cu-Zr合金在变形温度为300～450℃和应变速率为0.001～1s-1条件下的流变变形行为,获得了等温恒速单轴方向热压缩变形过程的真应力-真应变曲线,建立了流变应力本构方程。结果表明:在实验范围内,该合金高温压缩时均存在稳态流变特征且属于正应变速率敏感材料;在较低温度和较高应变速率条件下,流变应力除了与应变速率、变形温度有关以外,还与变形量有关;可用包含Arrhenius项的Zener-Hollomon参数描述该合金的高温压缩流变行为,基于热模拟试验提供的真应力-真应变数据,可得出流变应力σ解析表达式中A、α和n分别为2.09×106s-1、0.019MPa-1和5.075,其热变形激活能Q为112.66kJ/mol。
The flow stress features of novel super-high strength Al-Zn-Mg-Cu-Zr alloy containing were studied by isothermal compression at 300-450 ℃ and strain rate of 0.001-1 s^-1. The true stress-true strain curves of isothermal constant-speed uniaxial hot compression deformation were obtained, and flow stress constitutive equations were established. The results show that the alloy has steady-state flow characteristics and belong to positive strain rate sensitive materials during hot compression deformation. At higher strain rates and lower temperatures, in addition to strain rate and deformation temperature, the flow stress is related to deformation. The flow stress of Al-Zn-Mg-Cu-Zr alloys during high temperature compression deformation can be described by Zener-Hollomon parameter including Arrhenius term. A, α and n in the analytical expressions of flow stress are 2.09×10^6 s^-1, 0.019 MPa-1 and 5.075, respectively, based on the true stress-true strain data from thermal simulation. The hot deformation activation energy of Al-Zn-Mg-Cu-Zr alloys during hot deformation is 112.66 kJ/mol.
出处
《稀有金属材料与工程》
SCIE
EI
CAS
CSCD
北大核心
2010年第A01期413-417,共5页
Rare Metal Materials and Engineering
基金
总装预研项目(51312050107)
重庆市科技攻关计划项目(2009AC4015)
