不锈钢表面激光诱导纳米化对氮碳共渗层组织及性能的影响  

Effect of Laser-induced Nanization of Stainless Steel Surface on Microstructure and Properties of Nitrocar-burizing Layer

作　　者：张道达 赵龙志 连勇 周洪波 吴孝泉 孟扬 ZHANG Daoda;ZHAO Longzhi;LIAN Yong;ZHOU Hongbo;WU Xiaoquan;MENG Yang(College of Materials Science and Engineering,East China Jiaotong University,Nanchang 330013,China;Jiangxi Institute of Mechanical Science,Nanchang 330002,China;Institute for Advanced Materials and Technology,University of Science and Technology Beijing,Beijing 100083,China;Jinan Shengyang High Temperature Material Co.,Ltd.,Jinan 250000,China)

机构地区：[1]华东交通大学材料科学与工程学院,南昌330013 [2]江西省机械科学研究所,南昌330002 [3]北京科技大学新材料技术研究院,北京100083 [4]济南盛阳高温材料有限公司,济南250000

出　　处：《表面技术》2024年第21期153-161,共9页Surface Technology

基　　金：江西省重点研发计划(20202BBEL53025,20212BBE53044);江西省教育厅科学技术研究项目(GJJ214701,GJJ2207504,GJJ2207510);南昌市模具表面处理与加工制造技术重点实验室项目(2021-NCZDSY-003)。

摘　　要：目的探讨不同能量的激光冲击诱导316L不锈钢表面纳米化,对氮碳共渗层组织结构及性能的影响规律。方法采用20、30 J等2种单脉冲能量分别对2组316L不锈钢样品进行激光冲击预处理,另外以无激光冲击预处理样品为对照,对上述3组样品同炉进行离子氮碳共渗(保持温度为480℃)。采用SEM、GD-MS、XRD方法研究氮碳共渗层的显微组织、成分及相结构,采用显微硬度仪、摩擦磨损机和电化学工作站对氮碳共渗层的硬度、摩擦磨损性能和抗腐蚀性能进行测试。结果经激光冲击强化的氮碳共渗层的横截面组织结构分别为近表面富氮SN层、中间粗晶变形层和内侧富碳SC层。在渗层中C原子浓度的变化曲线呈现S形,在渗层与基体交界处C原子含量达到最大值。此外,3组不锈钢样品均主要由S相和γ相组成。经过激光冲击后样品的氮碳共渗层S相的含量大幅增加,γ相显著减少。结论激光冲击能量为20 J的不锈钢样品的渗层具有经济性的物相组成和渗层厚度,兼具良好的耐磨和耐腐蚀性能,其实际应用价值较高。Stainless steel nitrocar-burizing is to dope nitride and carbon elements on the surface of stainless steel,so as to improve the wear resistance and corrosion resistance of the material.Laser shock hardening is a new surface strengthening technology which uses laser shock wave to produce plastic deformation on metal surface,increase the surface dislocation density,and improve the hardness and fatigue resistance of the metal surface.The change of metal surface microstructure caused by laser shock treatment is beneficial to the adsorption and diffusion of N atom in subsequent ion nitriding,so as to significantly improve the efficiency of ion nitriding.However,there are few researches about the effect of laser shock energy on the microstructure and properties of ionitrocarburizing layer.In this study,the 316 stainless steel surface was treated by laser shock with four different energy densities,followed by low temperature ionitrocarburizing,and the effects of different laser shock energies on the structure and properties of ionitrocarburizing stainless steel were analyzed by various characterization methods.Three kinds of impact energy of 0,20 and 30 J were used to laser shock the stainless steel,and then the stainless steel was treated at 480℃for ion nitrogen carburizing and subject to heat preservation for 5 h.The gas source was ammonia and argon+C4H4(9∶1)mixed gas and the ratio was 1∶1.The microstructure,composition and phase structure of the infiltration layer were analyzed by SEM,ED-MS and XRD.The hardness,friction coefficient and corrosion resistance of the permeated layer were tested by microhardness tester,friction and wear machine and electrochemical workstation.The three kinds of stainless steel specimens could be divided into three layers,including the outer fine crystal zone,the middle coarse crystal transition zone and the inner deformation affected zone.In terms of phase structure,the infiltration layer was divided into two layers,in which the outer layer was N-rich layer dominated by SN,and the i

关 键 词：激光冲击 奥氏体不锈钢 氮碳共渗 电化学 显微硬度 

分 类 号：TG156.8[金属学及工艺—热处理] TG142.1[金属学及工艺—金属学]