This paper discusses the process of high-velocity oxygen fuel (HVOF) spraying with modeling gas flow parameters and behavior WC-Co-Cr powder particles different fractions (up to 20 µm, 21–35 μm 36–45 μm). It was found that temperature stream reaches a maximum about 2700 °C, after which it gradually decreases, pressure in combustion chamber (before exit gases through nozzle) values, exceeding 400,000 Pa, at nozzle stabilizes 100,000 corresponds standard atmospheric pressure. The velocity...

Samples using powders of four different fractions, 15–20 μm, 20–30 30–40 μm and 40–45 were fabricated to investigate the wear resistance, corrosion resistance tribological properties 86WC-10Co-4Cr coating obtained HVOF method. The phase composition, microstructure elemental distribution analyzed X-ray diffraction, scanning electron microscopy energy dispersive spectroscopy techniques. hardness was measured on a Vickers microhardness tester, friction coefficient rate investigated tribometer,...

This paper studies the coatings deposited on a 65G steel substrate by electric arc metallization using 30KhGSA wire. The properties of obtained at 30 V, 40 V and 45 are discussed, including their microstructure, porosity, microhardness, coefficient friction corrosion resistance. experiments showed that possess layered structure formed sequential deposition metal microdroplets. It was found increase in voltage favors decrease layer density, microhardness improvement wear resistance At maximum...

In this paper, Cr3C2-NiCr metal-ceramic coatings obtained by high-velocity oxygen fuel spraying (HVOF) at various distances are studied. A detailed morphological characterization of the cross section was carried out using scanning electron microscopy (SEM) with backscattered electrons (BSE). It found that particle size chromium carbide Cr3C2 varies depending on deposition distance. Morphology analysis also revealed distribution pores, which is important for wear resistance coatings....

Arc spraying is one of the most effective and cost-efficient thermal technologies for creating high-quality protective coatings. This paper examines influence arc process parameters on properties steel The varied in this study included gas pressure, wire feed rate, distance from spray gun to substrate (standoff distance). Experimental evaluations focused surface roughness, thickness, porosity, structure, hardness techniques used these profilometry roughness measurement, scanning electron...

In this study, a surface hardening of AISI 52100 bearing steel was performed by ultrasonic nanocrystal modification (UNSM), and electrolytic-plasma thermo-cyclic (EPSM), their effects on the wear resistance were investigated. To evaluate impact these treatments resistance, friction tests under dry conditions conducted using ball-on-disk tribometer in accordance with ASTM G99. The microstructure samples before after treatment characterized scanning electron microscopy. micro-hardness respect...

This study investigated the influence of electrofrictional treatment on structure and hardness surface layers 40Kh 65G steels. Based results scanning electron microscopy, it was determined that during hardening (EFH) steel, a hardened layer, with microhardness 873 ± 37 HV0.1, formed. layer consisted two zones: surface-quenched zone, fine needle-like martensite austenite; heat-affected zone (transition layer), high-dispersion pearlite (troostite), smoothly transitioning into original...

The process of plasma electrolytic oxidation (PEO) allows to obtain multifunctional coatings with unique properties, including wear-resistant, corrosion-resistant, heat-resistant, electrical insulating and decorative. Therefore, the field application these is quite wide: medicine, aircraft construction, shipbuilding, instrumentation, automotive other industries. technology based on phenomenon micro-arc discharges promoting formation oxide layers metal surfaces. In this review technologies...

Samples of beryllium ceramics, with the addition micro- and nanoparticles TiO2, have been obtained by method thermoplastic slip casting. The microstructure batch consisting micropowders ceramics TiO2 sintered at an elevated temperature, has investigated. It was found that introduction leads to changes in mechanisms mass transfer formation, mobility interfacial grain boundaries increases, which formation elements a zonal shell structure. reduction intergranular increase density, hardness,...

The article presents the study results of electron irradiation effect on mechanical, tribological and thermal properties polytetrafluoroethylene (PTFE). allow a better understanding processes occurring in structure PTFE under reveal potential applications modified material with improved characteristics, high resistance mechanical strength. In this work samples were tested for wear stability. It was found that leads to significant increase microhardness by 1.5 times compared initial state....

This paper studies the effects of aluminium content in composite powder on structure detonation gradient coatings based NiCr-Al. Gradient were obtained by spraying with a gradual stepwise decrease barrel filling volume an acetylene-oxygen gas mixture from 50% to 25%. The elemental and phase composition, microstructure surface roughness NiCr-Al different 15%, 20%, 30% investigated. By varying obtained. study results showed that composition coating strongly depends mass fraction Al. In case...

This work are presented the research results of pulse plasma treatment influence on phase composition, hardness, roughness and element composition coatings bases Fe-TiB2-CrB2. The Fe-TiB2-CrB2 coating was deposited by detonation method. following pulse-plasma used to modify structure properties surface layers sprayed coating. mechanical experiments showed that hardness increased after treatment. On basis X-ray analysis, it has been established increase is connected with transformations in a...

In the present paper research results of influence nanoparticles TiO2 additions in range 0,1 — 2,0 wt. % on electrophysical properties oxide-beryllium ceramics (BeO + TiO2) made micropowders are presented. The characteristics synthesized modified with 30 microand electric current frequency 100 Hz MHz were studied by total complex resistance method (impedance). It is known that introduction addition to BeOceramics after heat treatment a reducing atmosphere accompanied significant increase...