In this paper cracking resistance and fatigue properties of five hard coatings – TiN, TiCN, TiAlN, AlTiN and nanocomposite nc-AlTiN/a-Si3N4 (nACo®) on tool steels WeartecTM and Vanadis 6 are evaluated by means of the cyclic Vickers indentation method. The analytical part covers an evaluation of damage evolution of the coated system versus the number of cycles. The comparative adhesion testing was conducted with the use of the Rockwell C technique. It was found that the type of cracks formed in the coated systems under cyclic loading depends on the Young modulus/hardness ratio. The data obtained permits to compare the cracking and fatigue resistance of the coated systems and to select the optimal coating for bulk and sheet metal forming tools.
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