Mechanical properties of Fe+SiC metal matrix composite fabricated on stainless steel 304 by TIG coating process

Abstract

In this work, metal matrix composite (MMC) coatings were fabricated by tungsten inert gas (TIG) arcing process on stainless steel AISI 304 with iron (Fe) and silicon carbide (SiC) powder. The influence of ceramic (SiC) on the wear behaviour and hardness of 10%, 20%, and 30% SiC by weight were investigated. XRD diffraction pattern revealed that the formation of metal silicide (NiSi, Fe2Si, CrSi2, and Ni3Si), iron carbide (Fe2C and Fe3C), and intermetallic compund (NiFe). EDX analysis confirmed the presence of Fe, Ni, Si, and C in coating. SEM was employed to investigate coating morphology and mode of wear mechanism. The magnified image reveals that fine-grained homogeneous structure has evolved in 20%-SiC, while agglomerated SiC particles in 30%-SiC coating due to improper dispersion of SiC in the coating during heating. Maximum microhardness was measured 663 HV0.1 in 30%-SiC and 660.5 HV0.1 in 20%-SiC; whereas average hardness was 507.7 HV0.1 and 499 HV0.1 respectively as compared to substrate hardness 220 HV0.1. Minimum wear loss was observed in 20%-SiC coating (wear height loss 301.5 μm), which is lower than two times as compared to substrate material (wear height loss 621.7 μm).