纳米多层结构实现硬质薄膜韧化的方法、机理与应用

摘要

硬质薄膜的韧化正成为气相沉积硬质薄膜研究和应用的重点.纳米多层结构设计是实现硬质薄膜强韧化的有效方法.本文介绍了纳米多层薄膜组元和韧化机理,讨论了周期、调制周期比、微观结构等子层因素对强韧化的影响,以及耐磨损、耐冲蚀场合的应用现状、问题以及原因.微裂纹在多层界面间偏折是纳米多层结构韧化的主要机理,但纳米多层结构界面越多,其裂纹萌生源越多,如果界面韧性较差,纳米多层结构会很快发生层-层剥离而失效.因此,纳米多层薄膜的韧化效果决定于界面的质量,而不是数量.必须获得高质量的层间界面,从断裂力学角度考虑抑制微裂纹的扩展,才能发挥纳米多层结构薄膜的优势.%The toughening of hard coating is becoming very important from engineering point of view.Nano multilayer structure is one of the effective way towards toughening.A comprehensive discussion on composition and toughening mechanism of structure toughening was presented.The effect of period,period ratio and microstructure on toughening,and the application of multilayer structure toughening in wear and erosion were also discussed.Micro-crack deflection is the main mechanism of toughe ning,but the more interface,the more initiation of cracks,results in spalling failure in case of little interfacial toughness.It can be concluded that interface quality rather quantity dominates toughening effect.In order to show the advantage of nano multilayer film,a good interfacial toughness must be obtained,and the blocking of the propagation of micro cracks should be considered from fracture mechanics point of view.