Methods of bonding metals together

Claim 2

The method defined in claim 1 wherein nickel and gold are two metals electroplated in successive layers on said cell wall edge portions.

Claim 3

For brazing together the elements of a sandwich panel comprising a honeycomb metal core, and a facing sheet of selected metal for brazing to each side of the core, at least one of which facing sheets is a felt metal comprising metal fibers, the method which comprises coating the cell walls of the core with electrolytic masking material of a type to prevent electroplating of the coated fibers, stripping the masking material from only the edge portions of the cell walls within the zone of the core immediately adjacent each side thereof tO which a facing sheet is to be bonded, electroplating at least two successive layers of different metals onto the stripped portions of the cell walls of the core, the metals used for such plating being selected from metals capable of brazing the cell walls of the core to the facing sheets, pressing one of the facing sheets against each side of the core, heating the core and facing sheets to a temperature to cause melting of the plated metals sufficient to braze the facing sheets to the core, while maintaining such pressure, on the facing sheets, and cooling the sandwich panel thus formed.