摘要
在变形温度为200～525℃、应变速率为0.008,0.013 s^(-1)的条件下,采用等应变速率法对AA5083合金板的拉伸流变行为进行了研究,并采用修正后的Backofen方程描述了该合金在此温度范围内的流变行为,建立了该合金应力随温度变化的本构模型。结果表明:AA5083合金在该应变速率和变形温度下,拉伸变形几乎未呈现应变硬化特征,流变应力只对温度和应变速率敏感,且随温度升高而降低,随应变速率的增大而升高;合金的流变阶段呈现出稳态,且随着温度升高该阶段延长,表现超塑特性;温度为200℃时,合金几乎未进入稳态阶段而出现明显应变软化,表现出动态再结晶特征。
The flow behavior of AA5083 alloy at the strain rate of 0. 008 and 0. 013 s-1 and temperature range from 200 to 525 ℃ was studied with the constant-strain-rate tensile tests. A up-dated Backofen equation was used to describe the tensile flow behavior of the AA5083 alloy, and the constitutive model of the alloy stress as the temperature change was established. The results show that the tensile deformation of the AA5083 alloy had nearly no strain hardening under the tensile condition. The flow stress was only influenced by temperature and strain rate, which reduced with increasing temperature and increased with enhancing strain rate. The tensile process behaved steady state which was prolonged with increase of temperature, showing superplasticity. When the deforming temperature was 200 ℃, the deformation of the alloy had mostly no steady-stat flowing and quickly appeared strain softening, showing continuous dynamic recrystallization.
出处
《机械工程材料》
CAS
CSCD
北大核心
2010年第6期89-91,96,共4页
Materials For Mechanical Engineering
