The multilayer effect in abrasion — optimising the combination of hard and tough phases
The multilayer effect in abrasion — optimising the combination of hard and tough phases
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DOI：
10.1016/s0257-8972(99)00151-6
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发表时间：
1999-09
影响因子：
5.4
通讯作者：
M. Berger;U. Wiklund;M. Eriksson;H. Engqvist;S. Jacobson
中科院分区：
文献类型：
--
作者：
M. Berger;U. Wiklund;M. Eriksson;H. Engqvist;S. Jacobson
研究表明，由较软但较韧的铬（Cr）和较硬但较脆的氮化铬（CrN）组成的多层PVD涂层的耐磨性超过了这两种相。这个明显的例外，简单的混合规则-磨损中的多层效应-被调查的物理机制，层厚度的依赖和影响，为磨料应用多层设计。采用反应磁控溅射技术在高速钢表面沉积了多层Cr和CrN。涂层在2.5μm金刚石磨料浆中具有显微硬度和磨料耐磨性。利用扫描电子显微镜和光学轮廓术对磨损表面进行了研究，揭示了微观磨损机理。建立了多层涂层耐磨性与层厚关系的物理模型。该模型虽然简化了，但与实验结果吻合得很好。铬层的优点是它们倾向于塑性变形，而不是因磨损而被去除；缺点是缺乏抗穿透性。然而，抗穿透性是CrN层的主要优点。从理论和实验两方面得出结论，多层效应可以解释为由于下部较硬的CrN层导致磨料在Cr层中的渗透深度降低。
In the present investigation it is shown that the wear resistance of multilayer PVD coatings, combining relatively soft but tough chromium (Cr) and harder but more brittle chromium nitride (CrN), exceeds that of both its phases. This striking exception to the simple rules of mixtures — the multilayer effect in abrasion — is investigated with respect to physical mechanisms, layer thickness dependence and implications for multilayer design for abrasive applications. Multilayers of Cr and CrN were deposited on high speed steel using reactive magnetron sputtering. The coatings were characterised with respect to microhardness and abrasive wear resistance against a slurry of 2.5μm diamond abrasives. The abraded surfaces were investigated by scanning electron microscopy and optical profilometry to reveal the microscopic wear mechanisms. A physical model for the layer thickness dependence for wear resistance of multilayer coatings was developed. Despite its simplifications, the model agrees very well with the experimental results. The advantage of Cr layers is their tendency to deform plastically rather than becoming removed by wear; the drawback is lack of penetration resistance. The penetration resistance, however, is the main advantage of the CrN layers. It was concluded, both theoretically and experimentally, that the multilayer effect is explained by the reduction of abrasive penetration depth in the Cr layers due to the underlying harder CrN layer.