(1. 重庆大学 国家镁合金材料工程技术研究中心，重庆400044；
2. 西南铝业(集团)有限责任公司，重庆401326)
摘 要: 对高硅铝合金光谱标准样品在应变速率为0.01~1 s−1、变形温度为350~500 ℃条件下的热压缩变形行为进行实验研究。结果表明：高硅铝合金热压缩变形中发生了明显的动态回复与动态再结晶，流变应力随应变速率的增加而增加，随温度的增加而降低；通过线性回归分析计算出高硅铝合金材料的应变硬化指数n以及变形激活能Q，获得了高硅铝合金高温条件下的流变应力本构方程；研究工艺参数(变形温度t、应变速率 )对晶粒尺寸的影响，确定最佳工艺参数：t=400 ℃， =0.1 s−1。
关键字: 高硅铝合金；热变形；流变应力；激活能
（1. National Engineering Research Center for Magnesium Alloys, Chongqing University, Chongqing 400044, China;
2. Southwest Aluminum(Group)Co., Ltd., Chongqing 401326, China）
Abstract:The flow stress behavior of high silicon aluminum alloy standard sample was investigated in the temperature range of 350−500 ℃and strain rate of 0.01−1 s−1. The results show that the dynamic recovery and dynamic recrystallization occur obviously during hot compression of high silicon aluminum alloy. The flow stress increases with increasing strain rates and decreases with increasing temperature. The strain hardening coefficient n and deformation activation energy Q are evaluated by linear regression analysis. And the flow stress constitutive equation of high silicon aluminum alloy during hot compression is obtained. The influence of the processing parameters (deformation temperature t, strain rate ) on grain sizes was studied. The optimal processing parameters, t=400 ℃, =0.1 s−1 were determined.
Key words: high-silicon aluminum alloy; hot deformation; flow stress; activation energy
