2524铝合金的热压缩变形行为

利用Gleeble-1500热模拟实验机,对2524铝合金进行高温等温压缩试验,实验变形温度为300～500℃,应变速率为0.01～10 s-1的条件下,研究了2524铝合金的流变变形行为。结果表明:合金流变应力的大小跟变形温度和应变速率有很大关联,2524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,而峰值流变应力随变形温度的降低和应变速率的升高而增大;在流变速率ε为10 s-1,变形温度300℃以上时,应力出现锯齿波动,合金表现出动态再结晶特征。采用温度补偿应变速率Zener-Hollomon参数值来描述2524铝合金在高温塑性变形流变行为时,其变形激活能Q为216.647 kJ/mol。在等温热压缩形变中,合金可加工条件为:高应变速率(>0.5 s-1)或低应变速率(0.01 s-1～0.02 s-1)、高应变温度(440℃～500℃)。

Flow Stress Behavior of 2524 Aluminum Alloy During Hot Compression Deformation

The flow stress behavior of 2524 aluminum alloy under hot deformation conditions was studied by isother- mal hot compression on Gleeble - 1500. The deformation temperature is rang from 300 - 500℃ and the strain rate range from 0.01^ - 1 s^-1. The results indicated that deformation temperature and strain rate atteet the size of flow stress, the flow stress of 2524 aluminum alloy increases with increasing strain and tends to be constant after a peak value, showing dynamic recover, and the peak value of flow stress increases with decreasing of deformation tempera- ture and increasing of strain rate. When the strain rate is 10 s ^-1 , and the deformation temperature is more than 300℃, the flow stress saw tooth fluctuates, showing dynamic recrystallization. The deformation aetivation energy of 2524 aluminum alloy under hot deformation is 216. 647 k J/tool when the flow stress described by temperature -eom- pensated strain rate Zener - Hollomon parameter. In the deformation of isothermal hot compression, the fleasible de- formation temperature and strain rate are high strain rate（ 〉0.5 s^-1 ）or 0.01 s^-1 -0. 02 s^-1 and 440℃ -500℃.