Microstructure and wear properties of laser clad Mo₂Ni ₃Si/NiSi metal silicide composite coatings

Mo₂Ni₃Si/NiSi wear-resistant metal suicide composite coatings were fabricated by laser cladding with 39Mo-35Ni-26Si(wt% ) powder as precursor on the substrate of austenitic stainless steel 1Cr18Ni9Ti. The Mo ₂Ni₃Si/NiSi composite coatings have a fine microstructure consisting of Mo₂Ni₃Si primary metal suicide dendrites and the interdendritic Mo₂Ni₃Si/NiSi eutectic structure. The dry sliding wear test indicates that the slight preferential wear of the Mo ₂Ni₃Si/NiSi eutectic structure occurs during the dry sliding wear process, resulting in the slight protrusion of Mo ₂Ni₃Si metal silicide reinforced phase. Due to the high hardness and strong covalent atomic bonding of Mo₂Ni₃Si metal suicide, no deformation and adhesion transfer were observed on the worn surface. Laser clad Mo₂Ni₃Si/NiSi metal suicide composite coating has an excellent wear resistance under the dry sliding wear test condition. Wear resistance of the composite coating is up to 56 times higher than that of the austenitic stainless steel 1Cr18Ni9Ti.