用裂纹密度参数评价PVD硬质涂层断裂韧性的研究

Fracture toughness evaluation of PVD coatings using crack density parameter

本文根据裂纹体自洽模型,推导出裂纹密度参数关系式,并采用压痕法,通过统计压痕域的裂纹几何,计算裂纹密度参数,以此来评价涂层的断裂韧性。涂层的裂纹密度参数与涂层的膜/基结合力有良好的对应关系,裂纹密度参数的设置对研究涂层的断裂韧性,揭示涂层的磨损与剥落过程,在理论上和工程上都颇有意义。

According to the self-consistent model for distribution of slit cracks in cracked solids, the mathematic representation of the crack density parameters was deduced. Fracture toughness evaluation of coatings was carried out by counting the geometry of cracks around the indentation and calculating the crack density parameter using the indentation method. The crack density parameters have a good corresponding relation with the film/substrate binding force of the coatings. The setting of crack density parameters is meaningful to study the fracture toughness and failure process of the coatings from theoretical and engineering perspectives.