离子渗氮和固溶复合处理制备深层含氮奥氏体不锈钢  

Preparation for Deep Nitriding Austenitic Stainless Steel by Complex Treatment of Plasma Nitriding and Solid Solution

作　　者：卢世静 孙斐[2] 缪小吉[2] 胡静[1,2] LU Shi-jing;SUN Fei;MIAO Xiao-ji;HU Jing(Jiangsu Key Laboratory of Materials Surface Science and Technology,Changzhou University,Changzhou 213164,China;Department of Mechanical Engineering,Changzhou Institute of Light Industry Technology,Changzhou 213164,China)

机构地区：[1]常州大学江苏省材料表面科学与技术重点实验室,江苏常州213164 [2]常州轻工职业技术学院机械工程系,江苏常州213164

出　　处：《表面技术》2018年第10期180-185,共6页Surface Technology

基　　金：国家自然科学基金项目(51774052);江苏高校优势学科建设工程项目(BA2016078)~~

摘　　要：目的通过离子渗氮和固溶复合处理制备深层含氮奥氏体不锈钢,获得硬度、耐蚀性和耐磨性等综合性能优良的奥氏体不锈钢。方法将304奥氏体不锈钢试样放在LD-8CL型直流等离子体渗氮炉内,在400 Pa下进行560℃、4h的离子渗氮处理,渗氮后进行1050℃、8h的固溶处理。使用HXD-1000TMC型显微硬度计、DMI-3000M型金相显微镜、D/max-2500型X射线衍射仪(XRD)、Thermo250XI型X射线光电子能谱仪(XPS)、CS350电化学测量系统和万能摩擦磨损试验机,对经过复合处理的304不锈钢的截面硬化梯度、截面组织、物相、表面成分、耐蚀性和耐磨性进行研究分析,验证此复合处理对获得硬度高、耐蚀性和耐磨性好等综合性能优良的奥氏体不锈钢的适用性。结果经过复合处理,不锈钢表面的氮原子数分数为1.56%,且为单一奥氏体相?N。?N所对应的衍射峰相对于不锈钢基体向左偏移,有效硬化层深达1.0 mm,不锈钢的表面硬度从基体的210HV0.025提高到308HV0.025。不但提高了深层含氮奥氏体不锈钢的耐磨性,而且提高了不锈钢的耐蚀性,腐蚀电位从基体的-0.534 V提高到-0.422 V,摩擦系数由基体的0.8降到0.7。结论离子渗氮和固溶复合处理适用于制备综合性能优良的深层含氮奥氏体不锈钢。工艺设计时,可以根据材料服役要求,选择合适的固溶工艺,从而获得满足不同综合性能要求的含氮不锈钢。The work aims to prepare deep nitriding austenitic stainless steel by a complex treatment of plasma nitriding and solid solution and then obtain the austenitic stainless steel with excellent comprehensive performance of hardness,corrosion resistance and wear resistance.304 austenitic stainless steel was put in a LD-8CL D.C.plasma nitriding furnace and plasma nitriding treatment was conducted at 560℃for 4 h in 400 Pa.Then,solid solution was carried out at 1050℃for 8 h.In order to verify the applicability to get excellent comprehensive performance for stainless steel by this complex treatment,cross-sectional hardness profile,microstructure,phase constituents,surface composition,corrosion resistance and wear resistance of 304 stainless steel after the complex treatment were investigated and analyzed by HXD-1000TMC microhardness tester,DMI-3000M metallographic microscope,D/max-2500 X-ray diffraction(XRD),Thermo250XI X-ray photoelectron spectroscopy(XPS),CS 350 electrochemical workstation and universal friction tester.The stainless steel through complex treatment had single expanded austenite phase(γN)and the nitrogen atomic concentration was 1.56%.The corresponding peaks ofγN shifted to the left to the stainless steel substrate.The effective hardening layer was 1.0 mm,and the surface hardness of the stainless steel increased from 210HV0.025 to 308HV0.025.Meanwhile,the complex treatment could improve the wear resistance and corrosion resistance of deep nitriding austenitic stainless steel.The corrosion potential increased from?0.534 V to?0.422 V and the friction coefficient of the nitrogenous steel decreased from 0.8 to 0.7.Complex treatment of plasma nitriding and solid solution can be used to prepare the deep nitriding stainless steel with excellent comprehensive performance.During technology design,appropriate solid solution parameters can be selected to prepare the nitriding stainless steel in conformity with various comprehensive performances based on the technical requirements of the components.

关 键 词：离子渗氮 固溶处理 XRD 深层含氮奥氏体不锈钢 耐磨性 耐蚀性 

分 类 号：TG156.8[金属学及工艺—热处理]