304不锈钢双活性屏离子渗氮

Double Active Screen Plasma Nitriding of 304 Stainless Steel

目的考察304不锈钢双活性屏离子渗氮技术的可行性及处理效果。方法利用双活性屏离子渗氮(DASPN)和普通直流离子渗氮(DCPN)两种技术对304不锈钢进行低温(420℃)硬化处理,对比分析两种工艺所得渗层的组织,对比研究两种工艺所得渗层的相结构、硬度和耐蚀性能。结果采用DASPN技术可获得比采用DCPN技术更为均匀、致密的渗层,渗层为单一S相层,硬度为763HV0.25。电化学测试表明,两种渗氮技术相比,DASPN处理获得的渗层耐蚀性能更优。结论采用DASPN技术对304不锈钢进行低温硬化处理,在试样距双屏的距离为70 mm时能够获得比DCPN更好的渗氮效果。该技术适于工业化推广应用。

Objective To explore the feasibility and thermal effectiveness of double active screen plasma nitriding（ DASPN） of304 stain steel. Methods Nitrided layers were prepared on 304 stainless steel substrate by low terperature DASPN technique and common direct-current plasma nitriding（ DCPN） technique,respectively. The morphology,phase structure,hardness and corrosion properties of the nitrided layers were comparatively analyzed. Results The nitrided layer produced by DASPN technique was more homogenous and compact compared with that produced by DCPN. It was a single S-phase layer and the hardness of the layer was 763HV0. 25. Moreover,the layer had a better corrosion resistance than that produced by DCPN. Conclusion The thermal effectiveness of 304 steel by DASPN technique was better than that of DCPN treatment,which is probably applicable to commercial process.