Enhancing heat transfer performance in 3D-printed integrated vapor chamber using composite structures

The demand for lightweight heat dissipation devices in aerospace and various other fields has spurred the development of aluminum-based vapor chambers. However, the surface of the aluminum particles is covered by a dense alumina layer, which poses a challenge in preparing the aluminum-based porous wick structure by sintering aluminum powder. In this study, two aluminum-based vapor chambers (60 mm x 50 mm x 4 mm) with distinct wick structures were integrated with the container utilizing 3D technology. The wicks of the vapor chamber included an aluminum-based grooved wick structure (GVC) and an aluminum-based grooved-porous composite wick structure (GPVC). A comprehensive experiment was conducted to evaluate the heat transfer characteristics of the vapor chamber, including startup performance, temperature uniformity, and thermal resistance, under different filling ratios and wick structure parameters. The working fluid was acetone. The results indicated that the GPVC demonstrated excellent startup performance under both low and high heat loads. The startup time of the GPVC was found to be 230 s, 30.3% less than that of the GVC under a heat load of 80 W. Furthermore, at a 60% filling ratio, the GPVC demonstrated lower thermal resistance and better temperature uniformity compared to the GVC. The GPVC achieved a minimum thermal resistance of 0.033 K/W with a maximum temperature difference of only 4.51 degrees C. This resulted in a reduction of thermal resistance by 47.5% and an improvement in temperature uniformity by 69%. The findings of this study provide valuable insights to the application of 3D printing technology to the production of aluminum-based composite porous wick structures.