作　　者： ; ; ; ; ;

机构地区： 中南大学材料科学与工程学院

出　　处： 《中南大学学报（自然科学版）》 2013年第5期1798-1805,共8页

摘　　要： 由含Zr的Al-Zn-Mg-Cu合金在不同变形条件下进行热压缩得到的真应力-真应变曲线,计算合金的热变形本构方程。基于动态材料模型构建合金的加工图,并分析功率耗散系数的变化和失稳区的范围。研究结果表明：该合金在热变形时存在2个失稳区,即低温失稳区（温度300-360℃、应变速率0.05-1 s-1）和高温失稳区（温度400-460℃、应变速率0.005-1 s-1）;在温度440-460℃,应变速率小于0.002 s-1的区域,最大功率耗散系数为0.52,该区域内的变形软化机制为动态再结晶。 True stress-true strain curves of A1-Zn-Mg-Cu-Zr aluminum alloy were investigated by hot compression thermal simulation test under different deformation conditions and used to calculate its constitutive equations. The processing maps were drawn according to the dynamic material model. Variations of power dissipation figures and scope of instability areas were analyzed. Two instability areas exist, the one is low temperature instability area, with 300-360 ℃ and 0.05-1 s-1 of strain rate; the other is high temperature instability area, with 400-460℃ and 0.005-1 s 1 of strain rate. Peak efficiency of power dissipation is 0.52 at 440-460 ℃ with strain rate less than 0.002 s-1 in the high temperature instability area, where dynamic recrystallization is main softening mechanism.

关 键 词： 铝合金 加工图 流变失稳 动态再结晶

领　　域： [金属学及工艺] [一般工业技术] [金属学及工艺]