Forming of the surface structure and properties of tool‘s ceramic inserts with improved abrasion resistance

摘要

Purpose: The purpose of this work is to explain the reasons for improved cutting properties of coated tools made of nitride and sialon ceramics by means of investigations into mechanical properties, including microhardness, adhesion and abrasive resistance of the coatings deposited and by means of investigations into the chemical composition and structure of the coatings.Design/methodology/approach: Investigations were performed in the framework of the work accomplished encompassing the following in the first phase: the development of a technology of deposition graded and multiphase coatings using the cathodic arc evaporation (CAE) methods; investigations were carried out in the second phase into the structure and properties of coatings deposited onto ceramic tool materials with the following required properties: high adhesion, microhardness, high resistance to abrasive, corrosive and diffusion wear in the working conditions of high-performance cuttings tools. Findings: The coating deposition technologies (coating systems) employed for coatings deposited in PVD processes of cathodic arc evaporation (CAE) and in a high-temperature CVD process on tool ceramics are eligible for widespread industrial applications. Practical implications: Investigations into the service life have allowed to select coatings with the best cutting properties: (Al,Ti)N, (Al,Cr)N, (Al,Cr)N+(Ti,Al)N and T(C,N)+TiN deposited onto sialon ceramics and (Ti,Zr)N, (Ti,Al)N, Al2O3+TiN (1), Al2O3+TiN (2), TiN+Al2O3+TiN, TiN+Al2O3, TiN+Al2O3+TiN+Al2O3+TiN deposited onto nitride ceramics exhibiting best cuttability, which is correlated with their high adhesion to the substrate and high hardness. The above-mentioned coatings enhance the lifespan of a cutting edge by up to 550% and for this reason, the coatings are eligible for widespread industrial applications in cutting tools.Originality/value: An original achievement of the work - as a result of the conducted cutting tests with varied technological parameters and based on the results of investigations of mechanical and structural properties - is that an application recommendation is proposed for the developed PVD and CVD coatings deposited onto ceramic tool materials for industrial applications