ELEMENT COMPOSITION COMPARISON OF ELECTRIC-SPARK COATINGS AND ELECTROSPARKSINTERED MATERIAL

Abstract

One of the promising methods of powder obtaining practically from any conductive material, including hard alloy, characterized by relatively low energy costs and cleanliness of the process, is method electroerosion dispersion (EED). Currently there is no full information on initial composition, regimes and environment impact on the properties of disperse systems and recommendations on the effective technologies providing their sintering and hardening in the scientific and technical literature. Thus this prevents from the use of this method. For sintered parts hardening, it is helpful to use electric spark machining (ESM). ESM is technologically flexibilite, cheap and it helps to obtain coverings with a wide range of properties. However, in many cases the properties of electrospark coatings depend both on the composition, structure and properties of the electrode material, and on the properties of the substrate material. Complex theoretical and experimental studies are required to develop a complex technology for the production of disperse systems using electroerosion dispersion method and their hardening by electric spark machining, charecterised by good stress-related properties and performance. The purpose of this work is to research the elemental composition of electrospark coatings and electroerosion sintered substrates made of high-speed steel. When the experiments were set up, a metal powder was obtained from the waste of high-speed steel grade P6M5 when using a device for electroerosion dispersion of conductive materials. The resulting electroerosion powder consisted of particles of a spherical and elliptical shape measuring from 25 nm to 50 μm. The average particle size of the powder was 19.72 μm, and the specific surface area was 16725.95 cm2 / cm3. The electro-erosion powder was pressed by a hydrostatic method using an EPSI press. The powder was poured into a rubber hermetical mold then it was placed in a hydrostat working chamber where there was a liquid pressure of 300 MPa created by means of a high-lift pump. Nabertherm VHT 8/22 GR. Sintering was held in a vacuum at a temperature of 1050 ° C for 2 hours . Electrospark coatings on sintered sample material made from electroerrosion high-speed steel were produced using VK8 electrodes and UR-121 machine. Using EDAX energy-dispersive X-ray analyzer, built into QUANTA 200 3D scanning electron microscope, spectra of characteristic X-ray radiation were obtained at various points on the surface of the sample and along the cross-section. Based on the conducted studies it was established that the main elements in the electrospark coating are iron, molybdenum and tungsten, and sintering was held in a vacuum at a temperature of 1050 ° C for 2 hours . Electrospark coatings on sintered sample material made from electroerrosion high-speed steel were produced using VK8 electrodes and UR-121 machine. Using EDAX energy-dispersive X-ray analyzer, built into QUANTA 200 3D scanning electron microscope, spectra of characteristic X-ray radiation were obtained at various points on the surface of the sample and along the cross-section. Based on the conducted studies it was established that the main elements in the electrospark coating are iron, molybdenum and tungsten, and in the substrate only iron and molybdenum. the substrate only iron and molybdenum. Based on the conducted studies it was established that the main elements in the electrospark coating are iron, molybdenum and tungsten, and the main elements in the substrate are only iron and molybdenum.