MICROANALYSIS OF ELECTROSPARK COATINGS BASED ON ELECTROEROSION POWDERS

The development of modern engineering requires improvement of quality, reliability and durability of parts, assemblies and mechanisms. One of the efficient ways to solve these problems is to applyf functional coatings obtained by the method of electric-spark alloying (ESA). Main electrode materials are mostly sintered hard alloys, which cost due to expensive tungsten in them is relatively high. To solve this problem, a VK8 (90%) hard alloy powder (as a main part) and 10% of high speed steel powder, Gr. R6M5 are proposed to be used as an electrode material. One of the promising methods to produce powders from almost any conductive material, including hard alloy and high speed steel wastes, is the method of electroerosion dispersion (EED), characterized by relatively low energy costs and an environmentally friendly process. The aim of this work is to perform a microanalysis of a steel 30KHGSA section substrate and electrospark coating obtained by electrospark alloying by UR-121 using electrodes of a mixture of electroerosion powders VK8 (90%)+R6M5 (10%), obtained by electroerosion dispersion of hard alloy and high speed steel wastes in illuminating kerosene. To obtain a micro and nano powder of hard alloy and high speed steel wastes a unit for electric erosion dispersing of conductive materials was used. Microanalysis was performed by means of an inverted optical microscope OLYMPUS GX51. The microanalysis allowed us to determine the shape and size of individual grains and their relative positions to identify the presence of inclusions and microdefects and to judge on the properties of the substrate (30KHGSA) and the coating (VK8+R6M5).