纯镍N6平面热压缩变形行为及加工图

利用Gleeble-3800热模拟试验机对纯镍N6在变形温度800~1100℃,应变速率5~40 s-1,应变量70%条件下进行了高温塑性变形压缩试验,分析纯镍N6高温高应变速率热变形行为,得到了材料在不同变形参数条件下的组织变化规律及流变应力变化曲线,利用动态材料模型绘制出了纯镍N6在不同应变条件下的热加工图.通过对组织及热加工图的分析研究,得出变形温度为1000~1100℃,应变速率为5~7 s-1或20~40 s-1以及变形温度为800~900℃,应变速率为5~10 s-1为纯镍N6材料高温高应变速率热变形的两个合理变形参数区间,在参数区间内N6组织均匀;而流变失稳区变形参数条件下得到的组织比较紊乱,晶粒大小不一.纯镍N6热变形后的晶粒尺寸随变形温度升高及应变速率减小而增大. 

Hot compression deformation behavior and processing map of pure nickel N6

Hot compression deformation experiment of pure nickel N6 was conducted on a Gleeble-3800 thermomechanical simulator at a deformation temperature range of 800 to 1100℃, a deformation rate range of 5 to 40 s-1 and at a deformation of 70%. The hot deformation behavior of this material was analyzed at high temperature and high deformation rate. The microstructural evolution and the flow stress curves were obtained at different deformation parameters. The processing maps were drawn by using the dynamic material model. Through analyzing the microstructures and the processing maps, two reasonable regions are introduced for processing pure nickel N6:the deformation temperature range of 1000 to 1100℃ and the deformation rate range of 5 to 7 s-1 or 20 to 40 s-1; the deformation temperature range of 800 to 900℃ and the deformation rate range of 5 to 10 s-1. In these two regions, the microstructure of pure nickel N6 is uniform, while in the region of rheological instability the microstructure is disordered and the grain size is varied. The grain size of pure nickel N6 after hot deformation goes up as the deformation temperature rises or the deformation rate declines.