论文部分内容阅读
利用Gleeble-1500热模拟机研究固溶态Mg-x Zn-y Er合金(x/y=6,x=3.0,4.5,6.0;y=0.50,0.75,1.00)在变形温度为200~450°C、应变速率为0.001~1 s~(-1)下的热压缩变形行为。研究结果表明,在热压缩变形过程中加工硬化和加工软化同时发生,并相互竞争,其中合金加工软化主要由动态再结晶引起。构建了Mg-Zn-Er合金的本构方程,该本构方程能比较精确地预测合金的峰值应力。添加Zn、Er合金化元素致使Mg-3Zn-0.5Er(合金A)具有较高变形激活能。在温度和应变速率的二维平面内建立了合金的热加工图,并提供了合金的最优加工条件(应变量为0.3,Mg-3Zn-0.5Er合金(合金A):380~430°C,<0.1 s~(-1);Mg-4.5Zn-0.75Er合金(合金B):380~450°C,0.01~0.1 s~(-1);Mg-6Zn-1Er合金(合金C):390~440°C,0.01~0.1 s-1)。与Mg-3Zn-0.5Er(合金A)和Mg-6Zn-1Er(合金C)相比,Mg-4.5Zn-0.75Er(合金B)表现较优的热加工窗口。
The solid solution Mg-xZn-yEr alloys (x / y = 6, x = 3.0,4.5,6.0; y = 0.50,0.75,1.00) were investigated by Gleeble-1500 thermal simulator at a deformation temperature of 200-450 C, hot compression deformation behavior at a strain rate of 0.001 ~ 1 s ~ (-1). The results show that during the process of hot compression deformation, work hardening and processing softening occur simultaneously and compete with each other. The softening of the alloy is mainly caused by the dynamic recrystallization. The constitutive equation of Mg-Zn-Er alloy is established, which can predict the peak stress of alloy more accurately. Addition of Zn and Er alloying elements resulted in higher deformation activation energy of Mg-3Zn-0.5Er (alloy A). A hot working diagram of the alloy is established in a two-dimensional plane of temperature and strain rate and provides the optimum processing conditions for the alloy (strain amount 0.3, Mg-3Zn-0.5Er alloy (alloy A): 380-430 ° C , Less than 0.1 s -1; Mg-4.5Zn-0.75Er alloy (alloy B): 380~450 ° C, 0.01~0.1 s -1; 390 to 440 ° C, 0.01 to 0.1 s-1). Compared with Mg-3Zn-0.5Er (alloy A) and Mg-6Zn-1Er (alloy C), Mg-4.5Zn-0.75Er (alloy B) showed a better hot working window.