Functional components that use etched channels to transport liquids are becoming increasingly popular in a variety of fluid management applications, such as diffusion bonded plate heat exchangers, mixers, reactors, heat sinks and fuel cells. Precision Micro has become a centre of excellence in the design and production of such components using LEEP, a precision chemical machining process that incorporates laser technology.
Plates are profiled and channels generated simultaneously in a single etch process, before being stacked and laminar bonded, or simply held under pressure to form a functional matrix. Precision chemical machining imparts no mechanical or thermal stress on the plate that could compromise its planarity (flatness). Alternative manufacturing methods such as CNC milling, stamping or laser machining, can generate thermal distortion and machining detritus that can compromise stack bonding.
The versatility of the etching process enables designers to vary the size and shape of channels and incorporate headers, collectors and port features, knowing that they can be produced economically without the need for extra process steps.
A further benefit of the process is the ability to control the etchant chemistry, which in turn controls the non-directional surface finish within the channels.
As well as achieving a four-fold improvement in pitch accuracy across an 800mm x 600mm sheet of components, the LEEP process guarantees top/bottom side alignment of component features. This enables highly accurate channels to be produced on both sides of the plate, and also simultaneously. In this way high channel densities can be achieved, and by interlacing top and bottom side channels, stack heights can be minimised and thermal transfer improved.
http://www.precisionmicro.com/55/processes/laser-evolved-etching-process
