经淬火和回火的马氏体不锈钢,原始奥氏体晶粒大小能影响它在高温或室温状态下的冶金和机械性能,因此人们对晶粒度很重视。已有多种腐蚀剂用来显示不锈钢中的各种显微组织。室温下用来显示晶界的最常用试剂是Cohen等人首先使用,而后又有其他人加以改进的苦味酸 The quenched and tempered martensitic stainless steel, the original austenite grain size can affect its metallurgical and mechanical properties at high temperature or room temperature, so people pay attention to the grain size. A variety of etchants have been used to display various microstructures in stainless steel. The most commonly used reagent at room temperature for the grain boundaries is Cohen et al first used, followed by picric acid others have improved