D. Pakuła

Structure and Properties of the Wear Resistant Coatings Obtained in the PVD and CVD Processes on Tool Ceramics

The paper presents investigation results of structure and functional properties of the hard wear resistant coatings obtained in the PVD and CVD processes on the Si3N4 nitride tool ceramics. Examinations of coatings structures were made using the transmission (TEM) and scanning (SEM) electron microscopes, microhardness tests, coating adhesion to the substrate with the „scratch test”, and the coatings abrasive resistance „pin-on-disc” test. Machining tests results and roughness tests results for the machined grey cast iron surface are also presented. The research carried out proved that depositing the hard, anti wear, multilayer coatings based on the Al2O3 and TiN layers onto the Si3N4 nitride tool ceramics with the PVD method results in obtaining better functional properties like extension of the cutting tool life, than in case of the uncoated nitride ceramics or coated with the PVD coatings and some CVD ones.

Investigation of the structure and properties of coatings deposited on ceramic tool materials

This paper presents the results of the investigation of the structure and properties of the coatings deposited with the PVD and CVD techniques on sintered tool materials: cermets, oxide Al2O3 ceramic and nitride Si3N4 based ceramics. The investigation includes the metallographic analysis using the transmission and Scanning Electron Microscope (SEM), chemical composition analysis, as well as the analysis of the mechanical and functional properties of the material. Tests were carried out on the multipoint inserts made from the ceramic tool materials based on Al2O3 and Si3N4 and cermets, both uncoated and coated with gradient, multicomponent and multilayer hard wear resistant coatings with PVD and CVD processes.

Structure and Properties of the Multicomponent and Nanostructural Coatings on the Sintered Tool Materials

This chapter presents a general characteristic of sintered tool materials, in particular sintered sialons, nitride ceramics, injection-moulded ceramic-metallic tool materials and cemented carbides and a general characteristic of their surface treatment technology and especially chemical vapour deposition (CVD) and physical vapour deposition (PVD) techniques. The results of our investigations in technology foresight methods concerning the development prospects of surface engineering of sintered tool materials are presented. In the next subsection, we discuss the outcomes of multifaceted research carried out with advanced materials engineering methods, including high-resolution transmission electron microscopy, into the structure and properties of multicomponent, graded and multilayer coatings on the investigated tool materials, including the newly developed injection moulded ceramic-metallic tool materials. Special attention was drawn to a one-dimensional structure of the studied PVD and CVD coatings and its impact on the properties of coatings.