Design of Electroforming
Metals Available For Electroforming
- Nickel
- Nickel Manganese
- Nickel Cobalt
- Nickel Cobalt Manganese
- Copper-OFC
- Copper-Structural
- Copper-Decorative
In addition to the metals listed above, American Galvano offers several secondary coatings to enhance desired properties such as hardness, reflectivity or environmental protection.
Electrodeposited Coatings
- Rhodium
- Palladium
- Palladium-Nickel
- Platinum
- Electroless Nickel
- Gold-Hard
- Gold-Pure
- Copper
Mandrel Types
There are four general headings for mandrel types:
Reusable
When the geometry of the part to be electroformed will allow separation of mandrel from electroform with out damage to either component. This is the economical choice for multiple copies of the same shape and usually the material choice is Aluminum, Stainless Steel, titanium or a previous generation Nickel electroform.
Expendable
When the geometry of the electroform does not allow for removal of the master from the electroform (mechanical locking). The materials of choice are: 6061-T6 Aluminum, High Temperature wax, epoxies and some plastics. In special applications exposed photopolymers, photo resists and SLA’s have also been used as mandrel materials.
Conductive vs. Non-Conductive
Conductive mandrels are usually metallic and as mentioned Aluminum, Nickel , Stainless Steels and Titanium are the usual choices. While Aluminum is suitable for Nickel Electroforming, it has some problems when used as a mandrel for Copper Electroforming. Bottom line Aluminum should only be used as a onetime mandrel for Copper electroforming. The only conductive non-metallic mandrel materials that we have experience with is Carbon/ Carbon composites or graphite, these are also materials which we can adherently deposit metals onto with goods results.
Non-conductive mandrels cover a large variety of materials. The common thread for this type of material is that it must accept metallization by chemical means only. Usually this is accomplished by either reduction (silvering or mirroring) or autocatalliticaly (electroless plating). Electroforms with low tolerances or attention to detail may also be metalized by conductive paints or fine ground metal powders such as silver or bronze rubbed into the surface. Once Metalized, the electroform is created by electrodeposition over the now conductive surface.
Some of the more common non-conductive mandrel materials are:
- 3D Printed Materials
- SLA’S, ABS, PLA, High Carbon PLA’S
- Wax
- Epoxies
- Some Plastics
- Ceramics
- Glass
- RTV
- Fiber Glass
- Plaster
Examples of such benefits include
- Better electroforms pricing and improved electroformed component reliability for production oriented customers.
- A jump start in the development of custom electroforms for new item and research oriented customers.