Bright and matt nickel plating

1. Characteristics and properties

Nickel is a silvery-white heavy metal. It is hard, forgeable, ductile and can be polished excellently. Like iron and cobalt, nickel is ferromagnetic, the hardness of matt and bright nickel layers is 200-400 HV 0.1. Nickel is relatively resistant to air, water and alkalis, but hydrochloric acid, sulphuric acid and nitric acid dissolve the metal especially at higher temperatures. Nickel coatings are characterised by high hardness and good wear behaviour, whereby both factors are higher the more finely crystalline the microstructure of the coating is. Bright nickel coatings generally have a higher hardness and thus a lower ductility than matt nickel coatings.

2. Benefits and areas of application

Nickel coatings are mainly used on iron, zinc, copper and their alloys. Nickel has a cathodic effect on zinc and iron, which is why only a dense, pore-free and crack-free, firmly adhering nickel layer guarantees a corresponding protective effect. Most nickel layers for corrosion protection require an additional chromium layer, which in turn is more noble than nickel. In conjunction with appropriate process control, high-gloss, levelling and ductile coatings are deposited. Galvanic nickel coatings are standardized according to DIN 50968.

3. Basic material

Nickel coatings are mainly used on iron and steel, zinc, aluminium, copper and their alloys.

4. Required delivery condition

The goods provided must be largely metallically bright. Residual oils or residual impurities must be removable with conventional aqueous alkaline degreasers. Oils containing silicone, alkali/alkaline earth and high-pressure additives must be avoided at all costs.

5. Pre-treatment

Deposited bright nickel layers form a shine. For this reason, they are ideally suited as an intermediate layer on copper in order to give the component the corresponding gloss in the Cu/Ni/Cr bond.