Folded Fin Heatsinks
Folded Fin heat sinks are a good solution when looking for a medium to high density fin structure that is short in height (<2"). Generally formed from either copper or aluminum, a long sheet of material is folded back and forth to produce the fins. Depending upon the fin spacing and height, the fin tips can be flat or rounded. There are also special configurations, such as lanced offset and wavy, which can be used to improve the heat transfer ability of the heat sink. The fins are attached by either solder or thermal epoxy to a base usually made of aluminum or copper. Folded fin heat sinks can also be used inside a liquid cold plate as a way of increasing surface area and improving performance. Because of the manufacturing method, holes and cutouts in the fins can be time consuming to produce, so extra effort should be made in the design stage to minimize these features.
For maximum dissipation in air cooling versus the amount of occupied space, the concept of folded fin has no equal. Wakefield Thermal designs and manufactures folded fin heat sink assemblies for a variety of cooling applications, ranging from small microprocessors to large industrial power supplies. The assemblies consist of a flexible foil or sheet made of aluminum or copper, folded into a square wave or similar pattern, and attached to a conductive base plate. Attachment method can be conductive epoxy, soldering, or brazing, depending on cost and performance needs. Wakefield can also manufacture multilayer folded fin assemblies to further enhance thermal performance.