Room-temperature dry sliding wear behavior of γ-Ni/Mo2Ni3Si metal silicide “in situ” composites

Ni-base solid solution (γ) toughened Mo2Ni3Si metal silicide “in situ” composites were fabricated with different volume fraction of Mo2Ni3Si primary dendrite uniformly distributed in irregular Mo2Ni3Si/γ eutectic matrix. Results of room-temperature dry sliding wear tests indicated that the composite with a medium volume fraction of primary Mo2Ni3Si phase possessed the best wear resistance by optimum combination of the unique mechanical property of Laves phase Mo2Ni3Si and toughening effect of ductile γ phase. The primary wear mechanism is microplowing and soft-abrasion of the interdendritic Mo2Ni3Si/γ and subsequent brittle fracture of the hard Mo2Ni3Si primary dendrites. Ductile γ phase provided good toughening effect to Mo2Ni3Si Laves phase during dry sliding wear process.