Effect of Spray Forming on the Microstructure and Wear Properties of Al–Si Alloys

In this study an attempt is made to investigate the effect of spray forming over chill casting. The microstructures of spray formed Al–12Si and Al–20Si alloys consisted of a fine dispersion of Si particulates of size ranging from 2–10 μm in Al matrix, whereas microstructures of chill cast alloys are coarser. The hardness is higher and wear rate is lower for spray formed alloys than that of chill cast alloys. The better wear and hardness properties of spray formed alloys are explained in light of their microstructural features evolved during spray forming and morphology of worn-out surfaces.