COMPARATIVE INVESTIGATION OF NICKEL-BASED METAL-CERAMIC STRUCTURES WITH CERAMIC PARTICLES OF TUNGSTEN AND BORON CARBIDES MADE BY THE SELECTIVE LASER MELTING METHOD

摘要

Development of functional coatings on metal parts, with a set of performance properties different from the basic material features, seems to be a promising trend in modern material sciences. The reason lies in permanently rising performance and respectively increasing demands to the part reliability and lifetime. Particularly, the short life of high-loaded parts in aggressive environment, increased temperatures, and abrasive wear is a problem. The present work deals with the optimization of the laser radiation action on the metal powder mixture NiCrBSi and metal-ceramic powder mixtures like NiCrBSi-WC and NiCrBSi-B4C with different metal-ceramic ratios. It is found that when the laser is in action, ceramic particles are reduced in size and are distributed uniformly over the entire volume of the metal matrix. It is demonstrated that 12 vol.% of ceramic particles added to the metal matrix increase the coating microhardness by 30%.