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现在划痕法用于评估簿涂层结合力已有一段时间了。本测试中，金刚石压头在不断加载（阶梯式或连续式）的情况下划过涂层表面，直至某一载荷，定义为临界载荷，L／C，明显的失效事件发生。如果这一失效事件意味着涂层剥落，那么临界载荷就可用于定性地测量涂层一基体的结合力。然而众所周知，会发生一些可能的失效方式并且它们中的仅有一些倚赖于结合力如何。其它失效方式依赖于涂层内塑变和断裂，而不是膜基界面处任何的结合失效，它们对于评估涂层质量，特别是在摩擦学方面的应用也同样是有用的。本文中，针对热生长氧和溅射氮涂层，研究主要与结合力有关的失效方式（剥落和翘曲）下的加载状态与涂层厚度之间的函数关系。根据这些观察来讨论所见失效方式产生的原因，以及以较为定量的方式来评估测试涂层／基体结合力的划痕法的使用价值。
Scratch marks have now been used to evaluate the cohesion of book coatings for some time. In this test, the diamond indenter is continuously loaded (stepped or continuous) across the coated surface until a certain load is defined as the critical load, L / C, and a significant failure event occurs. If this failure event means that the coating is peeled off, the critical load can be used to qualitatively measure the adhesion of the coating to a substrate. However, it is well known that some possible modes of failure can occur and that only some of them depend on how well they bind. Other modes of failure rely on plastic deformation and fracture in the coating rather than any binding failure at the film-based interface, and they are also useful for evaluating coating quality, especially in tribology applications. In this paper, the relationship between the loading state and the coating thickness under failure modes (spalling and buckling) that are mainly associated with cohesion is investigated for thermally grown oxygen and sputtered nitrogen coatings. Based on these observations, we discuss the causes of the observed failure modes and the usefulness of the scratch method to evaluate the test coating / matrix bond in a more quantitative manner.