Abstract
This paper investigates the wear mechanisms of rotary mining cutters operating under abrasive and impact loading conditions and presents science-based approaches to improving their service life. During the study, gas metal arc welding (GMAW) hard-facing technology was applied to produce wear-resistant coatings using flux-cored wires EnDOtec DO351, EnDOtec DO332, and EnDOtec DO*11. Structural carbon steel C45, widely used in mechanical engineering, was selected as the base material. Hardfacing of experimental samples and cutting edges of rotary cutters were carried out using a CNC-controlled robotic three-axis system developed at AGH University of Science and Technology (Krakow, Poland). A comprehensive analysis, including metallographic, mechanical, and hardness were performed to determine the structural features and strength characteristics of the obtained coatings. In addition, the elemental composition of the deposited layers was analyzed using energy-dispersive spectroscopy (EDS). Microstructural analysis revealed the formation of chromium-rich carbide phases, which ensure high resistance of the coating to abrasive wear. Microhardness measurements showed that the hardness of the hard-faced layer significantly exceeds that of the base metal, reaching a maximum value of 1705 HV. The obtained results confirm the high efficiency of hard-facing technology in improving the wear resistance of rotary mining cutters and enhancing the reliability of mining machine working elements. The scientific novelty of this work lies in the comprehensive evaluation of the structural features of coatings obtained using GMAW technology and their influence on wear resistance.