joining methods

friction welding

How thick a parasite is allowable? Capillary attraction can be used various ways.

I would like to stay at greater than 85% footprint efficiency. For large areas this is very easy but our application is rather small ( <40cm^2 )and everything really eats into our footprint eff.

As i get it, you have an area of 40 square centimeters and desire to join two parts with a joint thickness of less than 6 square centimeters?

Assuming 2 parts 2cm x 10 cm than we have a maximum allowable joint between them of 10 cm x .6 cm. .6cm is a trmenedously thick joint for most operations.

What is the material? What shape are the parts actually? Why bond them; strngth, electrical condutivity, hold them in place for fixturing, etc?

Tom

more in detail:

Our general design resembles a picture frame with 6 discrete windows encompassed by a shared boarder.

Outside dimensions are roughly 8cm x 5cm. The lands in between areas have to create a hermetic seal on the internal components below. See pic.
The overall ‘sandwich’ consists of (from top down) thin metal frame, compliant membrane and another thin metal frame. We have the option to either ‘over-mold’ the metal frames to keep them in compression or add a thin plastic overframe and US weld the sandwich between the plastic but the more additional pieces we use the less efficient the overall package becomes.

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It depends on the part. For example, if you want a metal on a plastic you might sputter the metal on followed by electroforming. Through this means the interfacial material can be zero (if you're lucky) or a few hundred angstroms (worst case). A variety of other processes can be used depending upon the material combinations you want and the structural configuration.