▎ 摘 要
Heat dissipation plays an important role in improving luminous efficiency and reliability for light emitting diode (LED) devices. In this paper, graphene/epoxy composite is synthesized and used as thermal interface material for LED heat dissipation enhancement. Experiment is conducted to test the interface resistances of the novel composite materials with different graphene mixing ratios. Moreover, the thermal performances and junction temperatures of LED device with and without such thermal interface materials are analyzed and compared to show the heat dissipation effect of the proposed composite thermal interface material. The results show that thermal conductivity of graphene/ epoxy composite increases with growing graphene mixing ratio and the interface resistance can be decreased by more than 70 % with the composite TIM. The case study indicates that junction temperature decreases from 72 degrees C to 67 degrees C for a 10 W power LED after using TIM, and such temperature difference becomes larger for higher LED power. Furthermore, with graphene/epoxy composite thermal interface material, temperature is distributed more uniformly in the heat sink, also benefitting LED heat dissipation. This work is important for practical heat sink design and optimization for LED equipment.