The hot deformation behaviour of one 7XXX series aluminium alloy, 7A04, has been studied by conducting isothermal hot compression tests with degree of compression up to 55% at the temperature ranging from 350 °C to 480 °C and strain rates ranging from 0.002 s⁻¹ to 20s⁻¹. Based on characteristic of the flow stress obtained from those tests, an extended Voce equation, which constant parameters were modified as Arrhenius-type type equation, was given and used to calculate the flow stresses under the conditions of the hot deformation. The parameters of extended Voce equation were determined by experimental results. The comparison between the experimental and predicted flow stress values at the hot compression parameters range indicated good agreement. The average absolute relative error, root mean square error and the correlation coefficient were found to be 4.9%, 4.8 MPa and 0.997, respectively, which confirmed the extended Voce model had good accuracy. Additional, a finite element simulation model of isothermal hot compression process was used to verify the new Voce equation and the results verified the accuracy of the new equation. The main softening mechanism of the hot deformation was dynamic recovery and was confirmed by optical microstructures.

一个7XXX系列铝合金，7A04的热变形行为，已经研究了通过与压缩高达55％，在温度范围从350℃至480℃和应变速率范围从0.002 S的程度进行等温热压缩试验^{- 1}至20s ^-1。根据从这些试验获得的流动应力的特性，给出了一个扩展的Voce方程，该方程将常数参数修改为Arrhenius型方程，并用于计算热变形条件下的流动应力。通过实验结果确定了扩展的Voce方程的参数。在热压缩参数范围内的实验和预测的流动应力值之间的比较表明了很好的一致性。平均绝对相对误差，均方根误差和相关系数分别为4.9％，4.8 MPa和0.997，这证明扩展的Voce模型具有良好的准确性。额外，利用等温热压缩过程的有限元模拟模型对新的Voce方程进行了验证，结果验证了新方程的准确性。热变形的主要软化机理是动态恢复，并通过光学显微组织得到证实。