Increased fluid transport
Increased fluid transport
This is a result of the broad porosity range of metal fiber wicks (between 50 and 85%), leading to high porosity.
A heat pipe transfers heat between two solid interfaces. A liquid in contact with a thermally conductive solid surface is turned into a vapor. This then travels along the heat pipe to the cold interface and condenses back into a liquid. Here it releases latent heat. Bekaert produces the wicking material inside the heat pipe to transport the condensed liquid back to the hot interface.
Key criteria for an efficient wicking material are: good thermal conductivity from heat source to cooling liquid; a capillary action to transfer the condensed liquid back to the heat source; and inertness to resist the high temperatures involved.
Bekaert’s wicking material for heat pipes is made of very fine metal fibers, randomly stacked and sintered to produce a porous capillary wick. Unlike regular powder wicks, the porosity of fiber wicks can reach a very broad porosity range (50-85%).
Depending on the wick parameters, Bekaert offers a wide range of alloys including copper, aluminum, nickel, stainless steel and titanium, with diameters ranging from 12 to 30 µm.
The challenge for designing new heat pipes is heat transfer at higher W/cm². As the metal fibers are easy to process, the size of the heat pipes can be significantly reduced to fit small and complex spaces. This meets the trend for miniaturized heat pipes.
