If your manufacturing company produces metal-based products, you already know how critical metal finishing is. Manufacturers use metal finishing to protect parts, improve performance, and enhance appearance across a wide range of products. With so many finishing options available, choosing the right one can feel overwhelming.
What Is Metal Finishing?
Metal finishing can be a physical, chemical, or mechanical process. It involves applying a metal coating or other treatment to the surface of a part. We refer to that part as a substrate. Despite the name, the substrate does not have to be metal. Many components that look like solid metal are actually plastic with a thin layer of metal finishing.
Industries that commonly rely on metal finishing include:
- Aerospace
- Automotive
- Electronics
- Medical
- Kitchen and Bath
- Musical Instruments
- Consumer Products
Metal finishing increases surface thickness, strength, and overall durability. It can also improve corrosion and chemical resistance, wear resistance, electrical conductivity or insulation, surface hardness, torque tolerance, and coating adhesion.
Which Metal Finishing Option Is Best?
Metal finishing refers to the final stage of part manufacturing, but it’s not a single process. Different finishing methods serve different functional and aesthetic goals. The key is matching the process to how the part will be used. Below is a high-level overview of common options.
Plating
Electroplating is the most widely used industrial plating method. Manufacturers apply it to both metal and plastic parts.
Plating on Plastics — ABS (Acrylonitrile Butadiene Styrene) plastics dominate commercial plating applications. The resin chemistry supports smooth, strongly bonded metal deposits.
To plate ABS and ABS/PC plastics, technicians first run the substrate through a pre-plate process to metallize the surface. They etch the plastic to create bonding sites, neutralize the etchant, and apply a palladium-tin film. After oxidizing the tin, they deposit electroless nickel to make the surface conductive. Electroplating then begins, typically layering acid copper, followed by nickel composites, and finishing with chromium.
Metal Plating — Decorative metal plating starts with surface conditioning and cleaning. Plating baths then deposit the desired metals onto the component. For functional finishes, technicians clean the part and place it into passivation baths to maximize corrosion resistance.
Gold Plating — ECF performs both decorative (hard) and reflective (pure) 24K gold plating for a range of applications.
Electroless Nickel Plating — Electroless nickel plating delivers uniform coverage, strong lubricity, excellent solderability, and high corrosion resistance. The process relies on a chemical reaction to deposit a nickel-phosphorus coating onto the substrate. Post-bake hardening can further increase wear resistance.
Unlike electroplating, electroless nickel plating does not require electricity.
ECF also provides decorative plating on plastics and both decorative and functional plating on metal substrates. Available finishes include gold, chrome, tin, nickel, and electroless nickel on materials such as steel, stainless steel, brass, aluminum, and more.
Trivalent Chrome
Trivalent chromium plating offers an environmentally responsible alternative to traditional chrome finishes while maintaining strong performance and visual appeal. ECF produces a range of bright and dark trivalent chrome finishes using both sulfate and chloride electrolyte systems, many of which meet automotive OEM qualifications.
In regions where roads are treated with calcium chloride, vehicles face higher corrosion risk. Trivalent chrome performs better than hexavalent chrome in these environments due to its superior corrosion resistance.
Paint over Chrome
Paint-over-chrome processes allow manufacturers to achieve unique colors and finishes. Black translucent and opaque finishes are especially common in kitchen, bath, and automotive applications.
ECF applies performance-based paints and coatings over both hexavalent and trivalent chrome. Customers can choose clear, translucent, or opaque finishes depending on design and performance needs.
Making Your Metal Finishing Choice
Before selecting a metal finishing process, clarify how you want the part to improve. Aesthetic upgrades often call for different solutions than functional enhancements like corrosion resistance or wear performance.
Cost also plays a role. Some processes cost more upfront but deliver longer service life or better performance, which can lower total ownership costs.
If you need help selecting the right metal finishing process, Electro Chemical Finishing can help. Our team brings deep experience across all major finishing methods. We work closely with customers to design custom finishing solutions that control costs, support production goals, and deliver reliable, high-quality parts.