Heat transfer performance analysis of an ultra-thin aluminum vapor chamber with serrated microgrooves

Abstract

With the advancements in communication technology and micro devices, the trend of miniaturization has resulted in severe challenges of heat dissipation. To address this issue, aluminum vapor chambers have emerged as a promising solution due to their low cost, lightweight, and high reliability. In this study, a novel ultra-thin aluminum vapor chamber, measuring only 2 mm in thickness and featuring support columns and micro-grooves, was developed using a one-piece extrusion process. The heat transfer performance of the chamber was investigated under water-cooled conditions by evaluating the effect of heat load, working inclination, and cooling water flow rate. The results demonstrate that the vapor chamber offers exceptional temperature uniformity, with a temperature difference (ΔT) of less than 7 °C when horizontally placed, and exhibits a minimum thermal resistance of 1.07 °C/W at a thermal load of 6 W. Positive tilt conditions enhance the heat transfer performance by 250 % through mass reflux, leading to a significant reduction in thermal resistance by half. Furthermore, the thermal resistance decreases as the inclination angle increases, and the vapor chamber demonstrates excellent anti-gravity performance. Cooling conditions have little effect on the heat transfer performance of the vapor chamber, and the idealized heat transfer performance can be achieved with a cooling water flow rate of 0.5 L/min.