Excellent thermal performance of gallium-based liquid metal alloy as thermal interface material between aluminum substrates

Abstract

To enhance heat transfer performance at the interface region between aluminum substrates, liquid metal alloy (LMA) Ga62.5In21.5Sn16 is used as thermal interface material (TIM). The pioneering work of this paper is the successful application of Gallium-based LMA on aluminum substrate through the formation of alumina film on its surface. The sandwich structure sample is prepared with gallium-based LMA fixed in the middle of two aluminum plates. The thermal properties of the sample, including thermal diffusivity and thermal conductivity, are measured by laser flash method (LFA457) and the thermal contact resistance (TCR) is also calculated. The results show that the presented method can not only avoid the intense reaction between Gallium-based LAM and aluminum, but also reduce the thermal contact resistance greatly. Compared with the sample without any interface material, the thermal diffusivity and conductivity of the sandwich sample using LMA Ga62.5In21.5Sn16 as TIM are increased by about 54.3 times under the pressure of 0.3 MPa. Furthermore, the TCR of the as-designed sample is reduced by 98.7% compared to the sample using TG-250 as the TIM.