Designation according to ISO 4527

ISO 4527 standard and coating designation

ISO 4527 "Autocatalytic (electroless) nickel-phosphorus alloy coatings" is the international standard for electroless nickel plating coatings. It defines a standardized treatment designation, specifying the main characteristics of the treatment to be applied to the workpieces.

Using this standard allows the designer and the customer to specify treatment characteristics unambiguously, minimizing misunderstandings and errors.

The type and characteristics of the traditional coatings — NIPLATE® 500, NIPLATE® eXtreme and NIPLATE® 600 — can be defined using the designation established in ISO 4527.

However, the standard does not cover composite coatings, namely NIPLATE® 500 PTFE and NIPLATE® 600 SiC.

Designation structure according to ISO 4527

The designation, to be shown in the title block of the technical drawing, is structured as follows:

Autocatalytic nickel coating ISO 4527 – a<b>/NiP(c)d[e(f)g]

• Part a<b>/: Refers to the base material, where a is the symbol of the alloy's primary element (e.g., Fe for steels) and b is the alloy designation (e.g., S235JR).
• Part NiP(c)d: Refers to the deposited electroless nickel layer, where c indicates the phosphorus content (e.g., NiP(7) for Niplate 600) and d is the minimum coating thickness in µm.
  • NIPLATE® 500 and NIPLATE® eXtreme have a nominal phosphorus content of 11% or NiP(11)
  • NIPLATE® 600 has a nominal phosphorus content of 7% or NiP(7)
  • NIPLATE® 500 PTFE, being a composite coating, does not have an official indication. It can be indicated as NiP(PTFE).
  • NIPLATE® 600 SiC, being a composite coating, does not have an official indication. It can be indicated as NiP(SiC).
• Part [e(f)g]: Refers to the heat treatment after electroless nickel plating, where e indicates the type (ER for dehydrogenation, HT for hardening treatment), f is the temperature in degrees centigrade, and g indicates the duration in hours.
  • Dehydrogenation at 150–180°C for 4 hours [ER(150)4]
  • Hardening at 260–280°C for 8 hours [HT(260)8]
  • Hardening at 330–350°C for 4 hours [HT(330)4]

Designation example

A Niplate 600 electroless nickel plating treatment with a thickness of 20–25µm and hardening treatment at 340°C for 4 hours, on 18NiCrMo5 steel, is designated as:

Autocatalytic nickel coating ISO 4527 – Fe<18NiCrMo5>/NiP(7)20[HT(340)4] - Thickness: 20–25 µm – Hardness: 1000±50 HV