Preparation of coatings simultaneously exhibiting high hardness and enhanced fracture resistance is a hot topic, as nowadays used ceramic protective coatings show difficulties to cope with increased demands due to their inherent brittleness. Material exhibiting seemingly contradictory combination of mechanical properties-high hardness and moderate ductility enhancing the fracture resistance-was recently predicted by ab initio calculations in the crystalline X2BC system. The presented study is focussed on the study of the influence of the C/W ratio on the microstructure, the content of different chemical bonds and the mechanical properties of W-B-C coatings prepared by magnetron sputtering at moderate temperature. It was shown that change of the deposition conditions to achieve different C/W ratios influences the energy flux and momentum transfer to the coating. The coating with the lowest C/W ratio experienced the highest energy flux and momentum transfer, which resulted in a dense coating microstructure. The microstructure progressively coarsened as the C/W ratio increased, i.e. as

The tribological properties of short range ordered W-B-C protective coatings prepared by pulsed magnetron sputtering Debnarova, S.

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Coatings are now frequently used on cutting tool inserts in the metal production sector due to their better wear resistance and heat barrier effect. Protective hard coatings with a thickness of a few micrometers are created on cutting tools using physical or chemical vapor deposition (PVD, CVD) to increase their application performance. Different coating materials are utilized for a wide range of cutting applications, generally in bi-or multilayer stacks, and typically belong to the material classes of nitrides, carbides, carbonitrides, borides, boronitrides, or oxides. The current study examines typical hard coatings deposited by PVD and CVD in the corresponding material classes. The present state of research is reviewed, and pioneering work on this subject as well as recent results leading to the construction of complete “synthesis–structure–property–application performance” correlations of the different coatings are examined. When compared to uncoated tools, tool coatings prevent direct contact between the workpiece and the tool substrate, altering cutting temperature and machining performance. The purpose of this paper is to examine the effect of cutting-zone temperatures on multilayer coating characteristics during the metal-cutting process. Simplified summary and comparisons of various coating types on cutting tools based on distinct deposition procedures. Furthermore, existing and prospective issues for the hard coating community are discussed.