High Thermal Conductivity Liquid Metal Composites Preparation by Electrical Control With Copper Particles

In this paper, two methods were used to prepare liquid metal-copper composites. The first one is the use of a NaOH solution in which copper powder is doped with gallium-based liquid metal (Ga₆₂In₂₀Sn₁₈) by magnetic stirring to generate SCu-GaInSn composites. The second one uses a simple electrical control treatment of gallium-based liquid metal for copper powder doping to generate a high thermal conductivity ECu-GaInSn composite. In this work, adding voltage to the gallium-based liquid metal helps the generation of gallium oxide on the surface of the liquid metal and reduces the surface tension, making copper particles more easily accessible to the interior of the liquid metal. In addition, the copper particles are used to build a thermally conductive pathway. The results show that the highest thermal conductivity of the composite obtained by electronically controlled copper powder entanglement doping gallium-based liquid metal is 71.08 W/(m·K). The gallium-based liquid metal has good thermal conductivity and wettability and can be used as a thermal interface material for chip heat dissipation. This work provides a new approach to designing liquid metal (LM)-based composites with enhanced thermal conductivity for a wide range of applications, including thermal management systems, 3D printing, flexible conductors, soft robotic systems, and wearable energy technologies.