Can parts be metal plated?
Most RP parts (SLA, SLS, FDM, Perfactory) can be metal plated, or electroformed. Similarly a variety of plastics from ABS to PEEK can be plated, but it is worth checking first.
This will usually require the application of an activator to the surface, followed by a layer of copper and then the material required. This latter layer is usually nickel, but chrome, silver and gold can also be applied.
Coating thicknesses can vary from a few micron through 200 micron. Thicker coats can be done, but part geometry becomes important if distortion is to be avoided.
Depending on the thickness to be applied and the application, it may be necessary to offset the component surface to allow for the metal thickness.
Alternatively we can remove the substrate altogether to leave very thin metal structures, way below what could be conventionally machined.
The resulting surface quality is very dependent upon the effort spent dressing the surface to be coated.