Hybrid Powder Metallurgical Production Of Heat Sinks Based On The Locally Dominant Heat Transport Mechanism

Abstract

Copper-based heat sinks are essential components in the cooling of electronic assemblies. In most cases, the aim is to increase the heat-transferring surface area in order to achieve a more efficient heat dissipation by applying Newton's law of cooling and using free and forced convection. However, this overlooks the fact that two different heat transfer mechanisms are interacting here. The base plate has a heat-conducting function to equalize any temperature differences, while the fins – the enlarged heat-transferring surface – transfer the heat to the flowing fluid via free and forced convection. It is therefore advantageous to differentiate between the heat spreader and the heat sink. Computational fluid dynamics simulations have shown that the thermal conductivity is more dominant in the base plate area to minimize local hot spots while free and forced convection dominates the situation in the fin area, where material properties do not play a big role.