基于7075铝合金时效强化机理分析的工艺优化

Process optimization based on analysis of aging strengthening mechanism of 7075 aluminum alloy

为了获得最佳的时效工艺和有效提升实验效率,以JMatPro仿真方法为基础,研究了7xxx系铝合金的时效强化机理,获得了铝合金的最佳时效工艺参数。通过JMatPro仿真得到时效过程中析出相的体积分数,获得了经典的JMAK动力学方程,再通过析出相长大模型得到时效过程中析出相的尺寸。然后,分别使用时效强化模型和JMatPro仿真方法计算时效后合金的强度,与时效强化模型相比,使用JMatPro仿真方法可以将合金强度峰值预测精度提高了0.72%;峰值时间预测精度提高了18.28%。最后,通过拟合JMatPro的仿真结果,获得了强度峰值、峰值时间与时效温度的关系表达式,为制定最佳的时效工艺参数提供指导。

In order to obtain the optimal aging process parameters of 7xxx aluminum alloys,the JMatPro simulation method was used as a basis to reveal the precipitation mechanism of the precipitated phases during the aging process.The volume fraction of the precipitated phase was obtained by JMatPro simulation,which was expressed in the form of the classical JMAK kinetic equation,and the size of precipitates during the aging process was obtained through the precipitation phase growth model.Then,the strengths of the alloy after aging were calculated by the aging strengthening model and the JMatPro simulation method,respectively.Compared with the aging strengthening model,using JMatPro simulation method can improve the prediction accuracy of alloy strength peak value by 0.72%,and the prediction accuracy of peak time by 18.28%.Finally,the relationships between peak value,peak time and aging temperature are obtained by JMatPro simulation method,which provides guidance for formulating the best aging process parameters.