There are numerous materials that can be coated with varying plating material. They include any tool steel, all stainless steels, beryllium, aluminum, carbide, brass, copper and pre-hardened steel such as the commonly used P-20 variety.
Almost anything is platable if you know what you are working with. One thing to keep in mind is temperature. All coatings in this article are applied at below 200xF. By using these low temperatures there is no concern with drawing down hardness or distorting the tool.
Another important fact is that it is possible to effectively plate over welds. Again, the key is to know your plating vendor’s capability level. A lot of platers can plate but not strip that plating to prep a mold for repair, for example. Welding should never be done over coatings; you’re just asking for more problems down the road. So make sure your plater can strip plating without any detrimental results.
Another useful tip pertains to plating on an angle surface on the inside diameter of a stripper ring to eliminate flashing plastic. We recommend micro welding the sharp edge prior to chrome plating. After grinding the inside diameter and top surface, the fact that the corner is steel assures that there will be no exposed chrome edge that is susceptible to chipping. It’s a very effective technique and can save you time and money in the long run.