Microstructure and Mechanical Properties of AIN Particles Reinforced Magnesium Matrix Composites with In Situ Synthesis Process

摘要

In this paper, in-situ AIN particles reinforced magnesium matrix composites were fabricated. The results show that the AIN phases can be in-situ synthesized in AZ91D alloy with the addition of Mg_3N_2. The microstructure and phases of the matrix alloys and the composites were investigated by OM, SEM and XRD. The hardness and mechanical properties of the matrix alloys and the composites were also obtained. Compared with those of the matrix alloy, the grains of composites were refined and the mechanical properties of composites were improved significantly. The microstructural analysis indicates that the AIN particles can act as the heterogeneous nucleation points of α-Mg phases in the composites. The strengthening mechanism of the composites with AIN particles was discussed.