High reliability and toughening mechanism of Cu-graphene nanolayered composite

Abstract

This dissertation explores the mechanical properties of metal-graphene nanolayered composites, with a particular focus on Cu-graphene systems. The integration of graphene layers within these nanolayered composites offers the potential to enhance their strength, toughness, and reliability under fatigue. Empirical studies have demonstrated that graphene serves as an effective obstacle to dislocation movement and crack propagation, consequently leading to notable improvements in their mechanical properties. The interfaces formed between the graphene and the metal layers play a crucial role in impeding dislocation motion and facilitating crack deflection and arrest. A novel fabrication method for Cu-graphene nanolayered composites is proposed, in which electrodeposition of metal and roll-based dry transfer of graphene is implemented for enhanced scalability. Furthermore, the impact of graphene patterning on interfacial adhesion and its influence on preventing delamination under bending fatigue conditions are thoroughly investigated. The optimized graphene patterning design demonstrates a good balance in crack absorption and prevention of global delamination. This dissertation is expected to provide valuable insights into the mechanical properties and optimization of metal-graphene nanolayered composites, facilitating their practical application in flexible electronics.