The Most Common Manufacturing Methods for Heat Sinks

The most common manufacturing methods for heat sinks are CNC machined, forged, die cast, zipper fin, extruded, bonded, and skived.

CNC Machined Heat Sink

Complex design options as well as high thermal conductivity are the two main benefits of CNC machined heat sinks. They are somewhat costly to manufacture and have a relatively slow manufacturing throughput rate, eliminating them as an option for inexpensive and/or high-volume products.

Forged & Die Cast Heat Sinks

Like forged heat sinks, die cast heat sinks offer low unit cost for high volume production. However, up front tooling cost is prohibitive for small to medium quantities. Die cast and cold forged heat sinks offer very good thermal performance. Forged heat sinks offer good design flexibility for intricate heat sinks while die cast heat sinks are limited to thicker fins making them ideal for enclosure lids used in natural convection applications.

Zipper Fin Heat Sink

A favorite when paired with heat pipes or vapor chambers, zipper fin heat sinks are low weight and offer the ability for thin, densely packed fins and ease of integration with two-phase devices. Vapor chambers can be used as the base of the fin array while heat pipes can run through the center of the fins to efficiently dissipate heat.  Tooling cost and unit price is reasonable.

Skived Fin Heat Sink

Excellent thermal properties, thin fins, a high fin aspect ratio, and low tooling cost are the hallmarks for skived fin heat sinks. However fins can easily become bent.

Bonded Fin Heat Sink

When a very large heat sink is required, bonded fins are likely the answer. Another advantage is the base can be made of a different material than the fins.