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通过磨损对比试验的研究指出,离子渗氮表面强化可显著地提高结构钢的耐磨性。除38CrMoAl 钢渗氮层带有脉状组织使其耐磨性提高不大外,35CrMo、40Cr 钢离子渗氮后的耐磨性分别是淬火、调质处理的两倍和十倍。研究结果表明,离子渗氮后不仅化合物层具有优异的耐磨性,而且当扩散层的硬度高于 HV600时,仍具有与化合物层相近的耐磨性。试验结果证实,气体软氮化的试样与离子渗氮相比,前者不仅由于表面疏松使其耐磨性降低,同时距表面不同层深处各点的耐磨性也均劣于后者。对磨损表面、表层和次表层进行金相显微镜和扫描电镜观测,表明离子渗氮层的磨损是以氧化磨损和疲劳磨损为主,调质样品的磨损则是属于粘着磨损与磨粒磨损。离子渗氮层γ′单相层的耐磨性高于ε+γ′双相的耐磨性。离子渗氮层的组织具有复杂的亚结构和微细界面。这种表面复杂的亚结构、表面少无氧化和疏松以及合适的氮浓度(5.5～7.5%),是离子渗氮件具有高硬度、高耐磨性和高强度的本质。
The comparative study of wear test points out that the surface strengthening of ion nitriding can significantly improve the wear resistance of structural steel. In addition to 38CrMoAl steel nitriding layer with a vein to make its wear resistance increased little, 35CrMo, 40Cr steel ion nitriding after the wear resistance are quenched and tempered twice and ten times. The results show that not only the compound layer has excellent wear resistance after ion nitriding, but also the wear resistance similar to the compound layer when the diffusion layer hardness is higher than HV600. The test results show that the gas nitrocarburized samples not only have lower wear resistance but also lower wear resistance at different depths of the surface than those of the ion nitriding. The wear surface, surface and subsurface metallographic and scanning electron microscopy observations show that the ion nitriding layer wear and tear wear-based oxidation and fatigue-based, quenched and tempered samples of the wear and tear belong to the adhesive wear and abrasive wear. The wear resistance of the γ ’monolayer of the ion nitriding layer is higher than the wear resistance of the ε + γ’ dual phase. The structure of ion nitriding layer has complex sub-structure and fine interface. This surface-complex substructure, with little surface oxidation and porosity and suitable nitrogen concentration (5.5-7.5%), is the essence of ion nitriding with high hardness, high wear resistance and high strength.