Microstructural Modification and Wear Behavior Improvement in Fe-C-Cr Hardfacing Alloys through Molybdenum Addition

The Fe-C-Cr hardfacing alloys were successfully deposited on Q235-carbon steel via arc surfacing welding. This study systemically investigates the influence of varying Mo additions (0.5-1.5 wt%) on the microstructure, mechanical properties, and wear resistance of the hardfacing layers. Microstructural characterization revealed that the deposited layers primarily consist of acicular martensite and M7C3 carbides. With increasing Mo content, the hardness of the alloy progressively increased, reaching a maximum value of 64.02 HRC for the 1.5 wt% Mo-doped alloy. Under reciprocal friction, a higher Mo content leads to an increased friction coefficient and reduced wear volume loss. More importantly, under high-stress three-body abrasive wear conditions, the 1.5 wt% Mo alloy demonstrated exceptional performance, exhibiting 133% greater wear resistance compared to conventional Cr26 high-chromium cast iron.