Scientists in two US laboratories have shown that three-dimensional printed aluminium heatsinks could be lighter and more compact in size – in other words, better than conventional heatsinks. They drew this conclusion from two closely linked projects at Oak Ridge National Laboratory and the University of Tennessee Knoxville:
One project proved- printed aluminium heatsink ensures not only equal but sometimes better thermal conductivity than a standard aluminium heatsink.
The second has developed genetic algorithms that make use of the freedom of shape available from 3D printing to design heatsinks that fit in the same space as their conventional cousins but work better.
In the first case, conventional heatsink aluminium (‘6061’, aluminium with <1 per cent Si and 1.5 per cent Mg) was compared with one printed by US firm Linear Mold AMS using an aluminium alloy developed for direct metal laser scintering (DMLS) which includes 10 per cent Si and 0.5 per cent Mg, according to ORNL.
At room temperature, the 6061 alloy had a thermal conductivity of 180W/mK, compared to 110W/mK for the printed heatsink – a lower figure here means worse conductivity and therefore a worse heatsink. At higher temperatures, they both varied in a roughly linear fashion, converging to 170WmK at 220°C.
For future simulation, the research team has created accurate theoretical models for both the printed alloy and 6061.