Al₂O₃ coatings were applied on the surface of 12Ch18N10T steel by the detonation method at different degrees of filling of the detonation gun. The aim was to study the influence of technological parameters on the formation of the coating’s structure, phase composition and tribological characteristics. The degree of filling the gun with a gas mixture (C₂H₂/O₂) varied from 53% to 68%. X-ray diffraction study showed that the content of α-Al₂O₃ increases depending on the degree of filling. The results showed that the hardness increases with an increase in the α-Al₂O₃ phase. When the gun is 53% filled with gas, the Al₂O₃-based coating has the hardness of 20.56 GPa compared to 58%, 63% and 68% fillings. Tribology tests have shown that the wear rate and friction coefficient of the coating is highly dependent on the degree of filling of the gun.

The coatings were formed by vacuum arc deposition. Unit cast target (cathodes) was used on the basis of 30 atm. % Ti, 35 at. % Zr and 35 atm. % Nb as the vaporized materials. Molecular nitrogen was used as the working gas. The thickness of the coatings in the experiments was 4.0 microns. The surface morphology fractograph fracture, track friction were investigated in a scanning electron microscope JSM-6390 LV. The use of multicoatings based on carbides is very promising to ensure the high performance properties of the complex, nitrides and silicides of transition metals. Findings - nanostructured coating of (Ti-Zr-Nb) N was obtained by vacuum arc evaporation cathode-cast in a nitrogen gas reaction medium. Multicomponent films have a pronounced columnar structure. Elemental composition was obtained by the vacuum arc deposition of coatings (Ti-Zr-Nb) N, depending on the physical parameters of the deposition process, in particular the pressure of the reaction gas nitrogen.

This chapter is devoted to experimental studies of changes in structural-phase blocks and tribological properties of combustion of layers of high-speed steels R6M5, R9, and R18 during electrolytic-plasma nitriding. Systematized experimental data on the effect of electrolytic-plasma nitriding on the structure, phase composition, and tribological properties of the surface layer of high-speed steels have been obtained. In addition, the patterns of formation of modified layers in high-speed steels during electrolytic-plasma nitriding, revealed in this work, can be used by researchers when choosing the modes of electrolytic-plasma treatment of alloyed steels, as well as when analyzing structural transformations of high-speed steels. Request access from your librarian to read this chapter's full text.

This chapter is devoted to experimental research on the investigated of the structural-phase, morphology, elemental composition, physical-mechanical, and tribological properties (friction, wear, and adhesion) of hard and superhard micro- and nanostructured coatings of systems based on (Zr-Ti-Nb)N, (Zr-Ti-Cr-Nb)N, and (Zr-Ti-Cr-Nb-Si)N were fabricated by vacuum-arc deposition in the nitrogen atmosphere. The authors in the work used advanced proven experimental research methods (SEM-EDX, TEM-EDS, XRD, SIMS, GDMS, PIXE, XPS, AFM, hardness measurements, and adhesion testing), as well as theoretical methods for analysing the results. Based on the results obtained, according to the experimental data, an optimal mode was selected that provides an increase in mechanical and tribological characteristics, and a method for vacuum-arc surface hardening was also developed. Such coatings seem to have prospects as protective ones for couples of friction and cutting tools. Request access from your librarian to read this chapter's full text.

This chapter presents an analytical review of literature sources devoted to research on the rapid heating of steels using various heat sources; in particular, on plasma surface hardening of materials. The results of studying the effect of a hardened surface layer during plasma hardening in the cathodic mode on the mechanical and tribological characteristics of grade two wheel steel are presented. Based on the experimental data obtained, a method for electrolytic-plasma surface hardening of wheel steel was developed and the optimal mode was determined. A description of the phase composition and morphology of grade two steel in the initial state and after electrolytic-plasma surface hardening is given. These descriptions are accompanied by images obtained by transmission electron microscopy. The authors present bright-field images and microdiffraction patterns obtained from these areas, as well as their dark-field patterns.

Scanning electron microscopy (SEM), EBSD-analysis, and X-ray structure (XRD) analysis were used to investigate the microstructure, morphology, elemental composition, phase composition, and crystal structure of M2 high speed steel after standard thermal treatment. It has been shown that the microstructure of the M2 high speed steel after hardening and three-time tempering consists of tempered martensite and solid carbide M6C-type and MC spherical shape. The volume fraction of carbides and their distribution have been defined. The main carbides in the study of steel after heat treatment – M6C and MС carbides who have a complex FCC lattice and space group Fd3m, have been established by X-ray structural analysis. Carbides are homogeneous and single crystal. EBSD-analysis method with the support of X-ray structural analysis has established that the bright carbides spherical shape M6C correspond to the composition Fe3W3C, and grey carbides spherical shape MC correspond to the composition of the VC.