Influence of Graphene Addition on Microstructure and Mechanical Properties of Homogenized Al4032–Graphene Composites Processed Through ECAP

In the present work, an Al4032 alloy reinforced with various contents of graphene (0, 1, 3, 5 wt.%) was fabricated via stir casting and an 8 h homogenization process. The Al4032–graphene composites were severely deformed by equal channel angular pressing (ECAP). The microstructure and fractography of composites at different processing stages have been investigated using optical microscopy and scanning electronic microscopy. The results reveal that the graphene sheets were dispersed homogeneously and Al4032 matrix grains were significantly refined with ECAP process. Moreover, the agglomeration of reinforcement with the addition of 3% and 5% of graphene in matrix alloy is also refined and bounded in the grain boundaries. The composites mechanical properties were assessed as a function of the number of passes in ECAP process. After 6 runs of ECAP, the hardness and tensile characteristics of the material improved considerably.