The wear results in the fact that 80% of parts and assemblies are out of commission. Protective gas-thermal spray coatings are widely used to reduce wear intensity. Required protective properties are achieved by optimizing coating composition and spray parameters. Coating efficiency may be significantly increased because of sprayed layers thermal treatment, which is empirically confirmed. Usually the thermal treatment is done by heating with gas flame, high-frequency current, and laser beam. Therefore, diffusion process along the boundary with base metal is activated, sprayed material densification occurs and material tensile strength is increased thus providing reduction in coating wear intensity. Object of offered researches are the coatings obtained plasma spraying of composite powders NiCr-Fe+50%Cr_3C_2, NiCr-Fe+80%Cr_3C_2 and a mechanical mixture of powders NiCr-Fe+50%SiC. Coatings sprayed on the unit "Plasma-Technik" (Switzerland) at the following modes: arc current of plasmatron - 300 A; distance of spraying - 120 mm; rate of plasma-formed gas - nitrogen - 50 liter per minute; rate of transported gas - nitrogen - 10 liter per minute. After spraying coatings subjected to impulse - plasma treatment. The plasma injector with a coaxial system of electrodes, which scheme is circumscribed in work [1], was served as source of impulses. As plasma-formed gas used nitrogen, the size of accumulated energy in the capacitive storage is 9×10~3 J.
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