Effect of Graphene on the Microstructure Evolution and Mechanical Properties of Al-10Si-2Cu-1.5Fe Aluminum Matrix Composites

GNPs-A380 composites with different GNPs contents (0.0 wt%, 0.5 wt%, 1.0 wt%, 1.5 wt%) are prepared by ultrasonic casting method. Using magnetic stirring for GNPs pre-dispersion treatment can effectively disperse GNPs and damage to GNPs is less. The distribution of GNPs in GNPs-A380 composites is optimal when the GNPs content is 1.0 wt%, and the microstructure is also optimal. The good dispersion of GNPs also results in the best refinement of the second phase. GNPs refine the second-phase GNPs-A380 composites by hindering the growth of the second phase. The refinement of the second phase reduces the stress concentration and crack spread in GNPs-A380 composites when loaded. The improvement of mechanical properties of GNPs-A380 composites is due to the dislocation strengthening and load transfer strengthening of GNPs.