常用冷作模具钢的气体渗氮与耐磨性研究

Study on Nitriding and Wear Resistance of Cold Working Die Steels

研究了9种常用冷作模具钢的气体渗氮层结构和渗氮速度，对比了不同材料渗氮层的耐磨性。结果表明，高速钢和基体钢渗氮层表面不易形成ε相层；Cr12型冷作模具钢高温（1110℃）淬火后渗氮，表面可形成ε相层，而中温（960～980℃）淬火后渗氮则在渗层中形成网状ε相。这三类高合金钢制的模具，均可利用气体渗氮提高耐磨性，且以Cr12MoV钢气体渗氮后的耐磨性最佳；低合金钢模具，不能用气体渗氮提高耐磨性。

The structure of nitrided layer and nitriding rate of nine kinds of cold work die steels have been studied. The wear resistance of different nitrided steels was compared. The results show that ε-Fe2-3 N layer is not found on the surface of nitrided high speed steel and matrix-steel,but it can be found on the surface of the Cr12 kihd steel dies which are nitrided after quenching at 1110℃. If the Cr12 kind steel is nitrided after quenching at 960~980℃,the netty nitride will be appeared in the nitrided layer. By gas nitriding,the wear resistance of cold work dies wlth a high hardness can be increased. But the wear resistance of lower alloy tool steel dies can not be raised by gas nitriding.