INVESTIGATION ON MICROSTRUCTURAL AND GEOMETRICAL CHARACTERIZATION OF COLD METAL TRANSFER HARDFACED INCONEL 718 ON MEDIUM CARBON STEEL

This study presents a compelling exploration of the microstructural and mechanical enhancements achieved with Inconel 718 hardfaced layers on AISI 1045 medium carbon steel through the advanced cold metal transfer (CMT) process. By precisely adjusting process parameters such as travel speed and wire feed rate, this research examines their effects on bead geometry and dilution for both stringer- and oscillation-type depositions. Microstructural analysis unveiled defect-free hardfaced layers, achieving seamless metallurgical bonding between the substrate and hardfacing material. Notably, oscillation-type deposition with optimized parameters (6 m/min wire feed rate and 20 cm/min travel speed) achieved an impressively low dilution of 3.38 %, surpassing stringer-type deposition in quality. Furthermore, hardness testing highlighted a significant improvement in the surface durability as oscillation-type deposition reached 254 HV, while the value of the substrate was 172 HV. SEM-EDX analysis confirmed the inclusion of critical alloying elements such as nickel, niobium, and molybdenum, reinforcing the hardfaced layer’s robust composition. These findings underscore the CMT process’s capacity to fabricate high-quality, low-dilution Inconel 718 hardfaced layers, providing substantial resistance to corrosion and wear. The finely tuned parameters identified here offer valuable guidance for the industries seeking enhanced performance in demanding environments.