45钢离子氮碳氧三元共渗与QPQ处理对比研究EI北大核心CSCD

盐浴复合(QPQ)技术为公认的能同时提高金属材料耐腐蚀性和耐磨性的表面改性技术,但其推广使用受到环保制约。为开发绿色高效表面改性技术,探索了离子氮碳氧三元共渗(PNCO)技术,并与QPQ技术改性效果进行了对比研究。选择45钢为原材料,分别采用PNCO技术和QPQ技术进行表面改性。利用光学显微镜及扫描电子显微镜、XRD、显微硬度计、摩擦磨损试验机、浸泡腐蚀实验对两种表面处理试样的截面显微组织、物相、表面及截面硬度、耐磨性和耐腐蚀性进行测试和分析。结果表明,在510℃×4 h工艺条件下,PNCO处理获得的化合物层厚度为20.14μm,有效硬化层厚度为59μm,截面最高硬度为760HV_(0.05),磨损率为1.39×10^(-3)g·N^(-1)·m^(-1),腐蚀失重率为0.39%。XRD结果分析表明,PNCO处理后渗层形成了Fe_(x)N化合物和以Fe_(3)O_(4)为主的氧化物相。PNCO和QPQ对比研究发现,两者表层硬度、耐磨性及耐腐蚀性均相近。本研究为绿色高效表面改性技术提供了可行的研究方向。

Comparison study of plasma oxynitrocarburising and QPQ for 45 steel

QPQ (quench-polish-quench) is recognized as an effective surface modification technology which can improve the corrosion and wear resistance of metal materials. However, it is environmentally constrained in real application. In order to explore an environmental friendly and efficient surface modification technology, PNCO (plasma oxynitrocarburising) was developed and compared with QPQ technology for 45 steel. The cross-sectional microstructure, phase composition, microhardness profile, wear and corrosion resistance were tested and analyzed by optical microscopy, SEM, XRD, microhardness tester and wear tester etc. The results show that a compound layer thickness of 20.14 μm and effective hardened layer thickness of 59 μm, surface hardness of 760HV_0.05, wear rate of 1.39×10^-3 g·N^-1·m^-1 and corrosion mass loss rate of 0.39% were obtained by PNCO. The XRD results demonstrate that PNCO treated samples mainly contain Fe_xN compound and Fe₃O₄ oxide. A comparative study between PNCO and QPQ shows that the sectional microhardness, wear and corrosion resistance of the treating layers are the same level. The study provides a feasible research area for environmentally efficient surface modification technology.