Optimum conditions for pressureless infiltration of SiCp preforms by aluminum alloys

The optimum parameters for processing aluminum silicon carbide metal matrix composites via pressureless infiltration of porous SiCp preforms are described. These optimum parameters were obtained by using a carefully designed experiment in which the effect of critical processing parameters on pressureless infiltration was investigated quantitatively. The parameters examined included: SiC particle size, infiltration time, preform height, % SiC in the preform, and Si coating on the SiC particles. The contribution of each of these parameters and their interactions to variation in density, modulus of elasticity, and modulus of rupture of the composites were determined and used to project the optimum processing parameters. Al/SiCp composites were produced using the conditions that were projected to produce optimum modulus of elasticity and their modulus of elasticity was measured. The results show excellent agreement between the projected and measured values.