Folded Fins: Corrugated sheet metal in either aluminum
or copper increases surface area and, hence,
the volumetric performance. The heat sink is then
attached to either a base plate or directly to the heating
surface via epoxying or brazing. It is not suitable
for high profile heat sinks due to the availability and
from the fin efficiency point of view. However, it allows
to obtain high performance heat sinks in applications
where it is impractical or impossible to use extrusions
or bonded fins.