薄膜涂层材料界面纯剪破坏标准试验法的开发

界面强度是薄膜涂层材料的最重要的性能指标之一，目前尚缺乏有效的测量方法。测量界面强度的主要困难在于寻求一种便于试验的试件形状和加载方式，使得界面上能够产生不同的应力状态，即在不同的剥离应力和剪应力比的状态下发生破坏。本文采用有限元数值分析（ABAQUS），研究了几种具有简单几何形状的试件的界面应力，并基于大量的数值试验，设计了剪应力为破坏支配因素的试件形状和加载方式，并且给出了便于应用的最大界面剪应力的经验估算公式。该经验公式可以适用于各种材料组合和薄膜涂层的厚度。研究结果表明，通过对薄膜涂层材料试件的基体引入缺口以产生应力集中，进行普通的四点弯曲试验，可以进行剪应力占支配地位的界面破坏试验。利用本文提出的试件形状和相应的最大界面剪应力经验公式，可以通过破坏试验简单地得到界面的剪切强度。

Development of Pure Shearing Destructive Standard Test Method for Coating Materials

Interface strength is one of the most important properties of coating materials. There are no effective evaluation methods yet. The main difficulty is to find a test method with simple specimen shape and loading style to cause different interface stress modes, that is, normal stress and shear stress dominated modes. The interface stress of several simply shaped specimens and loading conditions was studied by means of finite element method analysis (ABAQUS). Based on the numerical analysis, the specimen shape and loading condition for shear stress dominated mode were designed, and the empirical formula to calculate the interface shear stress was proposed. The empirical formula can be applied to various material combinations and coating layer thicknesses. The results reveal that four-point-bending test by introducing a notch in the substrate can lead to the shear stress dominated mode. Therefore, the shearing strength of interface can be easily evaluated by such a test.