Abstract Metal matrix composites produced by Ni3Al intermetallic particles dispersed in a ductile aluminum matrix, with outstanding properties, are increasingly used in aerospace and structural applications. In manufacturing of metal matrix composites using powder metallurgy blending and milling are important factors. They control the final distribution of reinforcement particles and porosity in green compacts after compaction, which strongly affect the mechanical properties of the produced PM materials. This paper studies different conditions for producing composite powders with the aim of uniform dispersion of Ni3Al particles in aluminum powders to present improved physical and mechanical properties. The results indicated that an intermediate milling time for fabrication of composite powder, better than prolonged and shortened ones, causes better microstructure and properties. It was shown that addition of 5 vol. % Ni3Al particles, produced by 15 hours mechanical alloying to aluminum powders, and then 12 hours blending operation provides an appropriate condition for producing Al-Ni3Al composite powder.

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