The aim of the work was to obtain corrosion-resistant and impact-resistant material for hardfacings the system Fe-Cr-Mn-Ti-C based with modified austenite-carbide structure through thermodynamic analysis of the nature of phase formation during cooling and solidification and experimental studies of the microstructure, hardness, abrasive wear resistance, ability to deformation hardening of electric arc hardfacings from powder electrodes materials. According to the results of the study of the polythermal cross section of the Fe-Mn-Cr-Ti-C system in the concentration range corresponding to the composition of the powder electrode materials, it was found that Ti doping leads to the formation of insoluble TiC in melt in the early stages of crystallization. Its presence provides grain refinning of the structure of austenite and austenite-carbide eutectic. The results of the study of the microstructure of the surface layer deposited by a powder electrode material of the Fe-Mn15-Cr15-Ti2-C2 system show that it consists of three structural components: elongated dendritic crystals of manganese austenite growing in the opposite direction to the heat gradient, dispersed TiC inclusions which are located in the central regions of the austenitic grains and the plate eutectic A + Cr7C3 located in the interdendritic space. The results of the determination of hardness and durability show that the effect of Ti on the hardness of coatings is negligible both before and after plastic deformation and is manifested mainly in increasing the microhardness of austenite. The effect of Ti content on abrasion resistance is more significant as it is observed to increase by 30%. Based on the studies, it was found that in the system Fe-Mn15-Cr15-C2 additives Ti in an amount up to 2 wt. % act as structure modifiers, contributing to a significant increase in abrasion resistance. Powder coated electric arc coatings of the proposed alloying system are characterized by corrosion resistance and deformation hardening (hardness after plastic deformation is 52 HRC), so they can be used to strengthen the work surfaces of briquetting presses for the production of fuel briquettes from waste products. Further research should pay attention to the choice of rational technological parameters of obtaining coatings of the developed alloying system and the features of their mechanical processing.

hardfacing, powder wires, high-alloy chromium, titanium carbide, deformation hardening

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Copyright (c) 2019 Pavlo Prysyazhnyuk, Iryna Semyanyk, Dmytro Lutsak, Lyubomyr Troshchuk