论文部分内容阅读
为了提高Custom 465马氏体沉淀硬化不锈钢的耐磨性,分别在440、480和520℃对580℃时效后的样品进行了2 h的盐浴渗氮,使用显微硬度计、X射线衍射仪、电化学工作站、球盘式摩擦磨损仪、表面轮廓仪、扫描电镜等设备,研究渗氮温度对Custom 465钢表面物相、硬度、渗层显微形貌、耐蚀性及耐磨性的影响.随着渗氮温度升高,耐蚀性逐渐降低,但表面硬度增加,520℃处理后表面硬度增大到1240 HV,较未处理试样的400 HV明显上升,渗层厚度达到22μm.440℃渗氮后表面物相为氮在马氏体基体中过饱和的α’N,点蚀电位降低约60 m V;480℃时有少量CrN相析出,引起点蚀电位降低约180 mV,同时磨损体积下降约43%;520℃时CrN相的含量明显升高,自腐蚀电位降低约70 mV,无明显的稳态钝化区,磨损体积降低82%,减磨效果明显.
In order to improve the wear resistance of Custom 465 martensitic precipitation-hardened stainless steel, the samples after 580 ℃ aging at 440, 480 and 520 ℃ were subjected to salt bath nitriding for 2 h. The microhardness and X-ray diffraction , Electrochemical workstation, ball disc friction and wear tester, surface profiler, scanning electron microscope and other equipment to study the nitriding temperature of Custom 465 steel surface phase, hardness, microstructure of the layer, corrosion resistance and wear resistance As the nitriding temperature increases, the corrosion resistance gradually decreases, but the surface hardness increases, the surface hardness increases to 1240 HV after 520 ° C treatment, which is obviously higher than 400 HV in the untreated sample, and the thickness of the coating layer reaches 22 μm. After nitriding at 440 ℃, the surface phase is supersaturated αN of nitrogen in the martensite matrix and the pitting potential is reduced by about 60 mV. A small amount of CrN precipitates at 480 ℃, resulting in a reduction of pitting potential of about 180 mV. At the same time, the wear volume decreased by about 43%. The content of CrN phase increased obviously at 520 ℃, and the self-corrosion potential decreased about 70 mV. There was no obvious steady state passivation zone and wear volume decreased by 82%.