Metallic tribological compatibility of laser clad Mo₂Ni₃Si/NiSi metal silicide coatings

Novel wear-resistant Mo₂Ni₃Si reinforced metal silicide coatings were fabricated on a substrate of austenitic stainless steel AISI 321 by laser cladding with Mo-Ni-Si alloy powders. Microstructure of the coating was characterized by optical microscopy (OM), scanning electron microscopy (SEM), X-ray diffraction (XRD) and energy dispersive X-ray analysis (EDS). Wear resistance of the coatings was evaluated under block-on-wheel dry sliding wear test condition at room temperature. Results indicate that the coatings have excellent wear resistance and tribological compatibility to a metallic counterpart under dry sliding wear test conditions coupling with conventional metallic materials because of the high hardness and strong atomic bonds of the ternary metal silicide Mo₂Ni₃Si with MgZn₂ type Laves crystal structure.