高耐蚀性316L奥氏体不锈钢低温盐浴硬化处理

Surface Hardening with High Corrosion Resistance of 316L Austenitic Stainless Steel by Low-temperature Salt Bath

利用低温盐浴氮碳共渗技术对316L奥氏体不锈钢进行了表面硬化处理,并对硬化层的组织和性能进行了分析研究。实验结果表明,奥氏体不锈钢低温盐浴硬化处理的温度和时间对硬化层的组织和性能都有重要的影响,奥氏体不锈钢硬化层中能否有碳化物和氮化物析出取决于处理温度和处理时间。处理温度在480℃温度下处理10h,即可获得具有S相结构特征的高耐蚀硬化层;在此温度以上盐浴硬化处理时,硬化层将会有铬的碳化物和氮化物析出,将会降低硬化处理后不锈钢表面的耐蚀性能。

Austenitic stainless steel 316L was processed using low temperature salt bath to harden its surface. The microstructures and properties of the carburized layer were investigated. The results showed that the microstructures and properties of hardened layers are significantly affected by the treated temperature and treated time. The precipitation of carbide and nitride from the hardening layers depended on the treated temperature and treated time. The Sphase characterized high corrosion resistant hardening layer could be attained when the sample was treated at 480℃ for 10 h. When the nitrocarburizing temperature exceeded the critical values, the chromium carbide and nitride began to precipitate. The corrosion resistance of the hardened steel surface was also weakened.