Oxidation Behavior of BN/(Al-Mg) Metal Matrix Composites

摘要

Metal matrk composites (MMCs) that consisted of Al-Mg matrix reinforced with initially added BN particles were fabricated using the pressureless infiltration technique, and their oxidation behavior was investigated at 500 and 550 deg C in air. Initially added BN particles were partly consumed to make A1N, as another reinforcing particles. Another reaction product was MgAlB_2 dispersoids. Despite of the presence of these reinforcing particles, the oxidation resistance was not good owing to the formation of MgO-rich scale due to the preferential oxidation of Mg in the MMCs. Detailed microstructures and oxidation mechanism of the prepared MMCs are proposed.