Enhanced compressive strength of graphene strengthened copper (G/Cu) composites

This study explores the compressive mechanical properties of copper composites reinforced with graphene. Graphene was synthesized on copper powders via plasma-enhanced chemical vapor deposition. Multilayer graphene formation has been substantiated by Raman analysis. Graphene-coated copper (G/Cu) powders were then subjected to pressing and sintering to fabricate G/Cu composites. The mechanical properties of G/Cu composites were investigated under compression from room temperature up to 400 °C in air. The results demonstrated a substantial improvement in the mechanical properties of G/Cu composites compared to monolithic copper. Specifically, the yield strength in compression of the G/Cu composite increased by 203% at room temperature and by 190% at 200 °C. At 400 °C, the yield strength enhancement exceeded 370%. Microstructural analysis suggests that the observed enhancements in G/Cu composites can be attributed to reduced porosity, smaller grain size, and inhibited dislocation motion at the increased grain boundary area (due to refined grain size) and graphene-copper interfaces.