The Search for New Super- and Ultrahard Materials: Go Nano!

Abstract

Super- (H ≥ 40 GPa) and ultrahard (H ≥ 80 GPa) nanostructured and nanocomposite thin films, which have been developed during the last two decades, are finding an increasing number of applications, such as wear-protective coatings on tools, hard and self-lubricant coatings for harsh and variable environment, for corrosion protection and others. Increasing interest receive materials with a high ratio of hardness to Young's modulus as mechanically adaptable coatings on machine parts, where their high compliance combined with high hardness reduce the wear. After a brief overview of the the recent search for new super- and ultrahard materialds I shall concentrate on the progress achieved in the understanding of the properties, preparation and industrial applications of hard and superhard nano-structured coatings on tools for machining (drilling, milling, turning), forming, stamping, injection moulding and the like.