An Investigation into Roughness of Electroformed Thin Nickel Foils

Electroforming is an electrodeposition process, similar to electroplating, but it differs from electroplating in two respects. In electroplating, the coating is metallurgically bonded to the substrate and is an integral part of the surface. In electroforming, metal is deposited onto a mandrel or mold nonadherently and its thickness is significantly more. So that the deposited article can be separated from the substrate and used as an independent part. Electroforming is an excellent method for manufacturing thin-walled products, such as metal foils, more economically than other manufacturing methods. On the other hand, nickel foil is widely used in resistance elements, printed circuit boards with welded connections, asbestos-free gaskets, and fire-resistant membranes. Since the roughness is an influential parameter in applications, in this paper, the accuracy of face and backside roughness of 100 micrometers thick electroformed nickel foils produced by a simple electroforming system has been investigated. So, after achieving sufficient process parameter, that is current density, the foils have been produced by three distinct kinds of mandrels with different surface roughness. Because the mandrel'sroughness affects roughness of foil either foreside or backside, the variations of their roughness were measured. Finally, it has been concluded that in a mediocre electroforming system, with no expensive process parameters control such as atmosphere control, the accuracy of reproduction is within a fraction of a micrometer and the texture of mandrel's surface could be accurately reprinted.

An Investigation into Roughness of Electroformed Thin Nickel Foils Keywords:

electroforming , mandrel , electrodeposition , faceside , backside