Achieving balanced strength-ductility of heterostructured TiC/graphene nanoplatelets (GNPs) reinforced Al matrix composites by tuning TiC-to-GNPs ratio

Heterostructured Al/10 vol% (TiC-GNPs) composites were produced by powder metallurgy (PM) with different TiC-to-GNPs volume ratios. As the TiC-to-GNPs ratio decreases, the improved dispersion of TiC in the matrix is achieved and the heterostructure of the composite is optimised due to the decreased TiC fraction and increased interaction between TiC and GNPs. Besides, compressive properties of the composite are improved significantly, and a balance of the significantly increased strength (sigma YS of 481.0 MPa and sigma UCS of 651.4 MPa) and reasonably remained ductility (epsilon f of 10.9%) is achieved in the Al matrix composite reinforced with 8.5 vol% TiC and 1.5 vol % GNPs (A4) based on the optimised TiC-to-GNPs ratio and optimised heterostructure. However, the compressive properties decrease dramatically when the GNPs content reaches 2 vol% because of the presence of GNPs agglomerates.