【摘要】 发现微量Ｍｇ、Ｃｒ 和Ｃｏ 元素对ＭｏｎｅｌＫ５００型的高温塑性具有明显的改善作用， 实验合金在高温下表现出一定的超塑性。测定了超塑性的应变速率敏感指数ｍ 值和形变激活能， 发现合金在超塑性变形时激活能较低。超塑性变形可能是一个扩散所控制的过程。通过微量杂质在晶界偏聚的断裂功计算表明， Ｍｇ、Ｃｒ 和Ｃｏ 具有改善ＮｉＣｕ 基合金晶界结合力的作用， 与试验结果符合。更多还原

【Abstract】 Monel K 500 alloy has been modified by adding a small amount of Mg,Cr and Co elements to improve the mechanical property The test results show that the high temperature plasticity of the experimental alloy is much higher than the commercial Monel K 500 alloy and superplasticity appears at high temperature The index m of strain rate sensitivity and the activation energy Q of high temperature deformation were measured It is found that Q is small in the superplastic condition,It is suggested that the superplastic deformation is a diffusion controlled process The influence of Mg,Cr,Co additions on the fracture energy of the grain boundary has been calculated The results show that these minor elements increase the adhesion energy of grain boundary ,so the high temperature plasticity of Ni Cu base alloy is improved.更多还原