The processes described in the following show various techniques of galvano-forming upon cores. The field of application is diverse and extraordinary interesting in cases where conventional Methods have their scientific borders.
Basically one can distinguish between reusable and lost cores:
1. Reusable Cores:
Type A)
Type B)
Those are used if cores and the resulting stripping can be split. It’s important that corematerial and stripping material have different expansion coefficients.
The bigger the difference the easer core and stripping are to be split. Well suited for this purpose are acrylic glass, high-grade steel. aluminium and invar (nickel 36). Because the core aren’t used up during the process they can be used theoretically unlimited times.
2. Lost cores
For hollow bodies that can’t be deformed because of their spatial structure or their striping’s sensibility only the use of lost cores is possible. In most cases aluminium is used for this which is chemically dissolved after the stripping.
Advandages of this procedure:
+ Complex inner areas are produced through the treatment as negative shape (core)
+ Thinwalled pieces are possible (e.g. Cu pipes with a wallthickness of 100µm)
+ High temperatures are not needed for the production. Depending on the metalstripping between 0 and 100°C
+ The mounting of flanges is done warpfree without temperature stress.
Examples for the shape of lost cores:
+ Groove waveguides
+ Thermal elements
Examples for the shape of reusable cores:
+ Waveguidepassage
+ Nickelpipe
+ Copper-bushes