DLC: Flexible bridge across heterogeneous interface between alumina filler and epoxy resin matrix

The heterogeneous interface between filler and matrix within composites often acts as a bottleneck for material performance. Carbon materials, particularly Diamond-Like Carbon (DLC), are representing a novel trend in interface design. This study investigates the nanoscale mechanical and electrical properties of the heterogeneous interface between DLC-coated alumina fillers and an epoxy resin matrix. The results demonstrate that the DLC layer is instrumental in creating a harmonious modulus transition between materials that exhibit significant variance in their elastic moduli, characterized by an exponential relationship, and approximately 50% enhancement in interfacial adhesion. Additionally, the DLC layer exhibits elevated sensitivity in dielectric response, attributed to a small RC time constant. This interface transition technology offers new tools for composite material design.