304奥氏体不锈钢固溶渗氮的研究

Solid Solution Nitriding of 304 Austenitic Stainless Steel

在氮气中对304奥氏体不锈钢进行固溶渗氮,用电子探针测定了渗氮层的氮浓度分布,用扫描电子显微镜观察了渗氮层的金相组织。结果表明,固溶渗氮可以使304奥氏体不锈钢获得高氮奥氏体层;表面氮浓度随渗氮温度的升高和氮气压力的增大而增加,渗氮层深度随渗氮温度的升高和保温时间的延长而增加;渗氮后空冷和水冷时氮为固溶状态,炉冷时会析出氮化物。

Solid solution nitriding of 304 austenitic stainless steel in the nitrogen atmosphere was investigated. The distribution of nitrogen concentration and the microstructure of the nitrided layer were measured and observed by EPMA and SEM respectively. The results show that a high nitrogen content austenitic layer can be obtained on the surface of 304 stainless steel by solid solution nitriding; the surface nitrogen concentration increases with the increase of nitriding temperature and nitrogen gas pressure; the nitrided layer depth increases with the increase of nitriding temperature and holding time; nitrogen solubilizes in the state of solid solution in the 304 stainless steel after nitriding and cooling in air or water, while nitride precipitates in the case of furnace cooling.