What is composite plating

Composite plating is the process of adding solid particles to the plating solution and co depositing with metals or alloys to form a metal based surface composite material to meet special application requirements. According to the electrochemical properties between the coating and the base metal, the electroplating layer can be divided into two categories: anodic coating and cathodic coating. When the potential of the coated metal relative to the base metal is negative, forming a corrosive micro battery, the coating is called an anode, hence it is called an anodic coating, such as the zinc coating on steel parts; The potential of the coated metal relative to the base metal is positive, and when forming a corrosive micro battery, the coating is the cathode, so it is called a cathodic coating, such as the nickel and tin plating layers on steel parts.
Classified by purpose, it can be divided into:
① Protective coatings: such as Zn, Ni, Cd, Sn, and Cd Sn coatings, used as anti-corrosion coatings for atmospheric and various corrosive environments;
② Protective and decorative coatings: such as Cu Ni Cr, Ni Fe Cr composite coatings, which have both decorative and protective properties;
③ Decorative coatings: such as Au, Ag, and Cu. Sun imitation gold coatings, black chromium, black nickel coatings, etc;
④ Repairable coating: such as electroplating Ni, Cr, Fe layers to repair some easily worn parts with high cost or parts with poor processing quality;
⑤ Functional coatings: conductive coatings such as Ag and Au; Ni Fe, Fe Co, Ni Co and other magnetic conductive coatings; High temperature oxidation resistant coatings such as Cr and Pt Ru; Reflective coatings such as Ag and Cr; Black chromium, black nickel and other anti reflective coatings; Hard chromium, Ni. SiC and other wear-resistant coatings; Ni. VIEE, Ni. C (graphite) anti wear coatings, etc; Solderable coatings such as Pb, Cu, Sn, Ag, etc; Anti seepage carbon plating with Cu, etc.
Material requirements
The coating is mostly a single metal or alloy, such as titanium palladium, zinc, cadmium, gold or brass, bronze, etc; There are also diffusion layers, such as nickel silicon carbide, nickel graphite fluoride, etc; There are also cladding layers, such as copper nickel chromium layers on steel and silver indium layers on steel. The substrate materials for electroplating are not only iron based cast iron, steel, and stainless steel, but also non-ferrous metals, such as ABS plastics, polypropylene, polysulfone, and phenolic plastics. However, before electroplating plastics, special activation and sensitization treatment must be carried out.