一、绪言气体渗氮共渗处理时,在氨添加量多的情况下,试样抛光研磨后用光学显微镜观察,可在表面层看到主要沿奥氏体晶界分布的黑色组织,这早已为人所共知了。有报告说,这种黑色组织是渗入钢中的气体元素,在处理周期中以分子氮的形式从晶界逸出所造成的空穴;另一说法是,与气体渗碳一样,在反应进程中,与钢中的氧亲和力大的Si、Mn、Cr等合金元素,与扩散到表面层的氧化合,在奥氏体晶界生成氧化物而造成的;还有报告说,在高渗碳 I. INTRODUCTION Gas nitriding treatment, in the case of ammonia added in large quantities, the sample polished and polished with an optical microscope, the surface layer can be seen mainly along the austenite grain boundary distribution of black tissue, which has long been We all know. It has been reported that this black tissue is a gas element infiltrated into the steel and escapes from the grain boundary in the form of molecular nitrogen during the treatment cycle. Another way of saying is that like gas carburizing, , Alloying elements such as Si, Mn, Cr and the like that have a large oxygen affinity with steel are caused by the oxidation of oxygen diffused into the surface layer to form oxides at the austenite grain boundaries. It has also been reported that in the case of high-carburization