Effect of Molybdenum on Metallurgical and Wear Properties of Fe–Cr–C Hard facing alloy

Abstract

In this research, Surface hardening was performed by two types of Flux Cored Arc Welding (FCAW) filler metals based on Fe–Cr–C and Fe–Cr–C–Mo at the single, two and three- pass modes on the plain carbon steel. To evaluate the metallurgical and mechanical properties of hard facing layers, the optical microscope metallography, Scanning Electronic microscope, X-ray Diffraction test, hardness testing, Microhardness test and abrasion test was applied. Adding (1.1– 1.3) molybdenum to the Fe–Cr–C filler rod led to the formation of complex carbides of M₇C₃, in the microstructure. By increasing molybdenum, the wear resistance and hardness of the weld layers increased so that three-layers weld hardness reached to 62 HRC. Also, the hardness of complex carbides is 1299 HV which increased to 1596 HV by adding molybdenum.