Manufacturers that produce items made from ceramic or plastic materials must often implement additional steps to improve and protect their workpieces. Electroplating is a preferred finishing technique that deposits a metal coating onto the substrate. Electroplating ceramics or plastics provides benefits such as making the surface electrically conductive, improving strength and durability, increasing corrosion resistance and making a “dull” substrate look brighter.
The electroplating process is essentially the same with either material. It’s necessary to start with electroless plating using nickel or copper to provide a protective undercoating and “metalize” the surface. Unlike electroplating, the electroless method does not rely on electricity — instead, the deposition occurs via an autocatalytic chemical reaction. This coating will also promote the adhesion of the topcoat, which can consist of virtually any metal (gold, silver, copper, nickel, etc.) or metal alloy.
While the technique for electroplating onto ceramics or plastics is similar, there are some subtle differences the plating company must consider to ensure a successful outcome.
Ceramics cover a broad range of materials such as:
- Alumina, the common name for aluminum oxide, which is produced from bauxite
- Steatite, which is a derivative of magnesium silicate
- Zirconia, which comes from zirconium oxide
- Mullite, which is a rare silicate material
Most ceramics are lighter than glass, and they’re also more porous. Consequently, they typically require a thicker coating layer to achieve the desired result.
To produce an extremely thick coating layer, the plating company can start by depositing a molybdenum-manganese film followed by a barrier diffusion layer of electroless nickel. A third layer consisting of a precious metal such as gold or silver will create a tight seal that prepares the substrate for processes such as soldering or welding. A thinner coating is the better choice for applications that require electrical conductivity.
Plating Onto Plastics
The process of plating onto plastics for industrial applications began with the electroplating of chrome onto acrylonitrile-butadiene-styrene (ABS) in the automotive industry during the 1960s. These days, it’s possible to plate a wide variety of plastic materials such as Teflon, polycarbonate, nylon and polysulfone. However, chrome plating is no longer a widespread practice because of the environmental and health issues associated with hexavalent chromium. Many manufacturers now use nickel in place of chrome. Copper is a popular choice for applications that require electrical conductivity.
Proper surface treatment is essential to ensure the metal coating adheres to a plastic substrate. The pretreatment steps typically consist of cleaning, etching, neutralizing and activating.
SPC Can Assist You With Either Electroplating Process
Whether you’re looking to plate ceramic or plastic workpieces, you can trust SPC to execute the process flawlessly and affordably. Contact us to learn more about the process of electroplating onto these materials today.