A: A heat sink is a radiator that absorbs heat, usually from a printed circuit board assembly, and helps to dissipate the heat away from the electronic components.
A: Copper is an excellent conductor of heat and is used where weight is less of a consideration. Most aerospace heat sinks are aluminum because it is about 1/3 the weight of the same volume of copper.
A: Many heat sinks have very complex internal configurations that would be impractical to CNC punch, costly to tool for stamping, and time consuming for CNC milling, laser cutting or wire EDM. The etching process is indifferent to the complexity of the geometry. In addition, the etching process can easily accommodate surface features on the radiating side of the part to increase surface area and dissipation capacity.
A: Flexible heaters are resistive heating elements (like the coils on a stove or in a toaster) that are bonded to a flexible insulating material such as rubber, silicone, or polyamide (Kapton®).
A: The metal element material, often Inconel, stainless steel or copper, is first bonded to the material. To selectively remove the metal that is not part of the element design, etching is the practical solution. The element foils are often from .001 to .005” thick and would be very difficult to bond without damage after they had been cut out.