离子氮化对超高强度不锈钢CF170微观组织和力学性能的影响分析

Effects of Ionitriding on Microstructure and Mechanical Properties of Ultra-high Strength Stainless Steel CF170

研究了离子氮化对超高强度不锈钢CF170试件显微组织和力学性能的影响。金相和力学性能分析的结果表明:未渗氮试件金相组织中只有少量残余奥氏体存在,渗氮处理后金相组织中有大量残余奥氏体。经X射线衍射法检测,渗氮处理后残余奥氏体较未渗氮增加了4.7倍。渗氮后,试验钢抗拉强度、屈服强度、硬度和冲击功明显下降,但韧性提高。

The effects of ion nitriding on the microstructure and mechanical properties of ultra-high strength stainless steel CF170 specimen were studied. The results of metallographic and mechanical properties analysis show that, there is only a small amount of retained austenite in the metallographic structure of the unnitrided sample and a large amount of retained austenite in the metallographic structure after nitriding treatment. The results of X-ray diffraction show that, the content of retained austenite in CF170 steel is increased by 4.7 times compared with that of the non-nitrided sample after nitriding treatment. After nitriding, the tensile strength, yield strength, hardness and impact work of CF170 steel decrease obviously, but the toughness increases.