Experimental Study of Heat Sink Performances Using Copper Foams Fabricated by Electroforming

In this study, performance of heat sinks using the copper foams as heat-sinking material is investigated experimentally. The copper foam is fabricated by electroplating technique using polymer foam with pre-coated silver film as the precursors. The manufactured copper foams have the porosity, pore density (pore per inch, PPI), permeability and inertial coefficient in the ranges of 0.5∼0.8, 10∼40, 0.6∼ 2×10
⁻⁹
m
²
and 1.5∼3, respectively. Besides the copper-foam heat sink, performances of single-channel, plate-fin and pin-fin heat sinks are also investigated and compared with copper-foam heat sinks. The experimentally measured results show that the thermal resistances of copper-foam heat sinks are better than the single-channel, plate-fin and pin-fin heat sinks because of special flow features inside the porous media, enlarged heat-transfer area and enhanced heat transfer coefficient. Detail comparisons between the results of copper-foam heat sinks indicate that the thermal resistance of copper-foam heat sink decreases with the decrease in porosity and increase in pore density. The pressure drop crossing the copper-foam heat sink increases with the increase in pore density and decrease in porosity.