Electroless nickel plating (NiP)

According to DIN 50966 / ISO 4527 / ASTM B733 / MIL-C-26074E

Electroless (Chemical) nickel plating is an autocatalytic reduction of nickel (precipitation), the catalyst being the base metal (Fe or Al) deposit nickel and phosphorus (NiP) alloy coating. The main difference between classic electrolytic nickel plating and chemical nickel plating is that the chemical nickel plating is done without the use of electricity, therefore without the use of anodes, as well as in the coating characteristics. Since no current is used, chemical nickel coatings are of equal thickness over the entire surface of the object (no unequal distribution of potentials along the edges), therefore, chemical nickel is suitable for objects of complicated geometry – cavities, pipes, holes, etc. The precipitated coating hardness of 550 HV (50-52 HRc) is much higher than the hardness of electrolytic nickel, and after thermal heat treatment, the hardness could be increased up to 1000 HV (67-70 HRc), similar to hard chromium, so the process can replace hard chromium in many cases – especially for small items.

Characteristics of electroless nickel (NiP):

• equal thickness of coating over the entire surface
• equal thickness of coating inside the pipe
• phosphorus content in the coating 7-9% or 10-12%
• very good corrosion protection
• amorphous (lamellar coating) is not porous
• high coating hardness – up to 1000HV
• high abrasion and wear resistance
• nickel plating of objects of complicated geometry
• nickel plating to a given tolerance without the need for subsequent grinding
• possible coating thickness up to 100 microns, with a tolerance of +/- 2 microns
• alternative to hard chrome plating
• base materials: steel, cast iron, aluminum, copper, brass, stainless steel

Electroless nickel coatings are increasingly used in the automotive and aerospace, shipbuilding, mechanical engineering, chemical, pharmaceutical, petrochemical, food, and electrical and electronics industries.

Electroless nickel coating is used for protection of various shafts, bearings, bores, nuts, bolts, machine elements, PVC injection molding tools, gears, fittings, pump parts, valves, hydraulic pistons and cylinders, molds, etc.

Maximum dimensions of objects that we can plate on steel, stainless steel, copper, brass:

  • length: 1.300 mm
  • height: 800 mm
  • width: 400 mm
  • diameter: 800 mm
  • weight of the part: up to 130 kg

On aluminium: 650 mm  x 350 mm x 350 mm