304不锈钢低温离子渗氮及氮碳共渗处理  

Low-temperature Plasma Nitriding and Plasma Nitrocarburing of 304 Stainless Steel

作　　者：缪跃琼 林晨[1] 高玉新[1] 郑少梅[2] 程虎[1] 

机构地区：[1]台州学院机械工程学院,浙江台州318000 [2]青岛理工大学机械工程学院,山东青岛266033

出　　处：《表面技术》2015年第8期61-64,102,共5页Surface Technology

基　　金：国家自然科学基金项目(51307091);浙江省科技计划项目(2013C1117);浙江省大学生科技计划项目(2015R430019)~~

摘　　要：目的研究304不锈钢离子渗氮层和氮碳共渗层的组织、硬度及耐磨、耐蚀性能,并考察渗层的磨损机理。方法利用离子渗氮及氮碳共渗工艺在304不锈钢表面获得硬化层,利用XRD,OM及共聚焦显微镜、显微硬度仪、电化学测试仪,分析处理前后渗层的组织、相结构及渗层的硬度及耐磨耐蚀性能。结果 304不锈钢氮碳共渗和渗氮层主要为S相层,在相同工艺条件下,氮碳共渗工艺获得的渗层为γN+γC的复合渗层,且厚度大于单一渗氮层。渗氮层和氮碳共渗层硬度约为基体硬度的3.5倍。在干滑动摩擦条件下,氮碳共渗层比渗氮层具有更好的耐磨性能;渗氮层的磨损机理为磨粒磨损的犁沟效应和断裂,氮碳共渗层的磨损机理为磨粒磨损的犁沟和微切削。电化学测试表明,渗氮层和氮碳共渗层的耐蚀性能均优于基体。结论 304不锈钢在420℃进行离子渗氮和氮碳共渗处理后,硬度和耐磨性能可大幅提高,且氮碳共渗处理效果更佳。Objective To study the microstructure, hardness and wear and corrosion properties of plasma nitrided and nitrocar-burized layers of 304 austenitic stainless steel, and investigate the wear mechanism of the layers. Methods A nitrided or nitrocar-burized layer was formed on 304 stainless steel substrate by low-temperature plasma nitriding （ PN ） or plasma nitrocarburizing （ PNC） technique. The phase structure, hardness and wear and corrosion properties were comparatively analyzed with XRD, OM, microhardness tester and electrochemical measurement system. Results The nitrided or nitrocarburized layer consisted of expanded＆amp;nbsp;austenite （ S-phase） . The composite γN＋γC layer was formed by PNC technique with larger thickness under the same process con-dition. The hardness of the two layers was 3. 5 times higher than that of the substrate. The wear property of nitrocarburized layer was better than that of the nitrided layer under dry sliding friction condition. The wear mechanism of PN layer was ploughing actions and fracture, while the wear mechanism of PNC layer was ploughing actions and micro-cutting. The corrosion resistance of both the nitrided and nitrocarburized layers was better than that of the substrate as revealed by electrochemical test. Conclusion PN and PNC treatment at 420℃ could effectively improve the hardness and wear resistance of 304 stainless steel, and the treatment of PNC was better.

关 键 词：304不锈钢 离子渗氮 氮碳共渗 S相 耐磨性能 耐蚀性能 

分 类 号：TG174.445[金属学及工艺—金属表面处理]