Effect of Matrix Alloying and Reinforcement Coating on Porosity Nucleation in Metal-Matrix Composites

Abstract

The mechanism of porosity nucleation in pressure infiltration casting of metal matrix composites is investigated. Five interfacial configurations are considered for a variety of matrix/reinforcement systems. Interfaces with negative curvature such as cavity are found to be potential sites for porosity formation. The Al/Al2O3 system is most susceptible to porosity nucleation for the systems considered. Appropriate matrix alloying such as Mg in Al/Al2O3 system, and Mg and Cu in Al/SiC system and reinforcement coating such as Cu coating on SiC, could be effective for suppressing porosity formation.