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Aerospace industry seeks to develop high performing coatings for erosion protection. TiN or TiAlN hard coatings deposited by physical or chemical vapor depositions (PVD or CVD) are used with considerable success. However, the performance of such coatings is generally found empirically through the measurement of the minimum erosion loss. In the present work we use advanced finite element methods for studying the erosion mechanisms and for predicting the coating behavior in simulated erosion conditions. The calculation variables include the impact angle and velocity, the particle size and shape, and the mechanical properties of both the target and the impacting particle. Specifically, we rank the coating performance based on the local stress response to a solid particle impact. Using these approaches, as the first step, we evaluate the erosion resistance of a new category of erosion resistance coatings, namely the superhard nanocomposite systems such as nc-TiN/a-Si3N4 and nc-TiCN/a-SiCN. As the second step, we evaluate the erosion resistance of multilayer structures in which we optimize the sequence of the individual layers and their respective thickness, while using experimentally determined film macroscopic properties such as hardness, Young’s modulus, intrinsic stress and toughness. The performance is compared with the behavior of standard TiN coatings on stainless steel substrates. We demonstrate that the finite element design of film architecture, combined with tailored mechanical properties of individual nanostructured components of the film systems, opens new opportunities for highly performing erosion coatings. |