奥氏体不锈钢离子渗N组织及性能

采用辉光离子渗N技术对奥氏体不锈钢球阀进行表面氮化处理,改变其表面结构,提高表面耐磨性.选取三组离子渗N的温度,分别为400、440、480 ℃,渗N时间设置为12 h.采用扫描电镜、光学显微镜、X射线衍射仪、维氏显微硬度计和材料表面综合测试仪对渗N改性层的表面形貌、截面形貌、显微硬度和耐磨性进行测试.结果表明:离子渗N技术可以大幅提高奥氏体不锈钢的硬度和耐磨性.渗N温度为400 ℃时,渗N改性层最薄,耐磨性最差,480 ℃时渗N改性层最厚、耐磨性最好.

Microstructure and performance of austenitic stainless steel with ionic permeation of N

The surface nitriding treatment of austenitic stainless steel ball valve is carried out with technique of glowing ion permeation of N, so that its surface structure is changed and surface wear resistance is improved. Three sets of temperature of 400, 440 and 480 ℃ are chosen for ion permeation of N respectively, and the time of permeation of N is set to be 12 h. Scanning electron microscope, optical microscope, X-ray diffractometer, Vickers microhardness tester and material surface comprehensive tester are used to test the surface morphology, cross-sectional morphology, microhardness and wear resistance of the N-modified layer. The result shows that the technique of ion permeation of N will be able to improve greatly the hardness and wear resistance of austenitic stainless steel, when the temperature of infiltration of N is 400 ℃, the N-modified layer will be the thinnest and the wear resistance will be the worst, the N-modified layer nitrided at 480 ℃ will be the thickest and its wear resistance — the best.