Commercial and Industrial Metal Finishing Options
Arlington Plating Company provides commercial and industrial metal finishing options for a wide range of applications.
Nickel chrome plating, also referred to as, Decorative chrome plating continues to be the coating of choice for many metal finishing applications. Demand for chrome’s bright and lustrous finish continues to grow despite competition from other finishes, such as organic coatings and vapor deposition.
Chromium has withstood the competitive challenges due to its unmatched aesthetics as well as its superior technical capabilities, including exceptional corrosion performance, multi-substrate capability and supply-chain factors such as industrial scale, extensive installed applicator base, and long application history and experience. Chromium is widely used in the metal finishing industry for both decorative and hard-chrome plating.
Chromium plating has been carried out on a commercial basis since 1924. In decorative applications, the chrome is plated as a thin (0.25–0.8 μm) layer over nickel to provide an economical and highly corrosion resistant deposit. Most decorative chromium deposits are produced using hexavalent chromium electrolytes. Over the past two decades, processes based on trivalent chromium have gained increasing acceptance in the industry.
Bright chromium can be applied as continuous (regular) or discontinuous layers. Discontinuous deposits are formed by depositing the chromium on micro-porous (or micro-cracked) nickel plate. The selection of a continuous or discontinuous layer depends on the level of corrosion resistance required.
Failure of bright chromium plate is often due to deep pits developing as a result of corrosion starting at random cracks or pores in the chromium surface. Corrosion is an electrochemical mechanism. Because these cracks or pores are relatively widely spaced, the current developed by the chromium/nickel couple is concentrated at a few points. Deep pits form at these points and rapidly penetrate through the nickel deposit and the component substrate. Micro-discontinuities (micro-cracks) across the surface spreads the corrosion current and slows the corrosion rate. Typically, articles plated to service condition 1/2 would use regular chromium plate, whereas plating to service condition 3 or above would use a discontinuous layer (ASTM B456).