ForMatter/Finishes/plate/Electroless nickel (EN)
finish_plate_electroless_nickel

Electroless nickel (EN)

plate · satin · EN plating, Ni-P plating, Kanigen

A nickel-phosphorus alloy that plates without electricity — every surface in the bath gets the same thickness, including the inside of holes and the back of recessed pockets. Mid-gray, satin, hard, used on aluminum molds, hydraulic valves, defense hardware. The conformal-coating workhorse.

Autocatalytic deposition: Ni²⁺ ions reduce on the part surface, hypophosphite donates electrons, every wetted surface plates uniformly (no current density variation). Phosphorus content tunable: low-P (2–5%) for hardness ≥600 HV after heat treat, high-P (10–13%) for corrosion resistance / non-magnetic. Thickness 5–50 µm typical. Conformal — coats blind holes and complex internal passages. Wears like a ceramic (~750 HV after 400 °C bake). The mold-tooling and food-equipment standard for aluminum substrates.

character — satin gray-white, dimensionally uniform, hard, neutral.

Finish properties

  • levelsatin
  • subcategoryautocatalytic nickel-phosphorus
  • applies tometal

Second life

reversibilitymoderate — plating can be stripped chemically and re-plated. PVD coatings strip with NaOH or specialty chemistry; electroplated layers strip similarly.
blocks substrate recyclingno
renewabilityshop-renewable — strip-and-re-plate is the canonical path for restoring worn plating. Common services are bumper rechromers, watch-case re-platers, and PVD re-coaters (Oerlikon, IonBond).

ASTM B488 / B456 / B689 plating standards; Powder Coating Institute and industry-association literature.

Citations