Properties of the Coatings Produced by Plasma–Powder Deposition of an Electroerosion R18 Steel Waste Powder

Abstract—The use of effective technologies and high-quality materials and the reduction of production costs are the main challenges for competitive domestic agricultural and automobile transport enterprises; therefore, the renovation of car parts and agricultural machinery from high–quality secondary materials is a priority direction in their development. The purpose of this work is to study a coating formed by plasma–powder deposition of a powder created by the electroerosion dispersion of R18steel waste. (Experimental) 40Kh steel rounded samples 40 mm in diameter are used as a substrate for plasma–powder surfacing. Scanning electron microscopy is used to determine the elemental composition of the formed coating. An Olympus GX51 optical microscope is used to determine porosity. The Vickers microhardness of the samples is determined using a DM-8 automatic microhardness analysis system. The friction coefficient of the surface of a plasma–powder coated sample was measured on a special-purpose Tribometer friction machine. (Results and discussion) The results of tribological tests of the friction surface of samples made of 40Kh steel and a plasma–powder coating from a mixture of 50% PZhV5 iron powder and 50% R18 steel waste powder indicate a high friction coefficient of the latter. The wear is characterized by smoothing the solid surface protrusions of a sample. (Conclusions) The equal ratio of PZhV5 and R18 powders in the mechanical mixture is found to be optimal. The main elements of the plasma–powder coating formed at this ratio of powders in a mechanical mixture are iron, oxygen, carbon, tungsten, and molybdenum. The average microhardness of the 40Kh steel base is 2.1 times lower than that of the coating. At a path of 500 meters, the average friction coefficient of the deposited coating is 0.146 and that of the base is 0.486.