ISO 27874:2008

Overview - ISO 27874:2008 (Electrodeposited gold coatings)

ISO 27874:2008 specifies requirements and test methods for electrodeposited gold and gold-alloy coatings used in electrical, electronic and other engineering applications. The standard covers coatings applied to metallic and non‑metallic substrates and defines how purchasers should specify coating composition, thickness, tests and acceptance criteria. It excludes coatings on threaded articles and on sheet/strip in non‑fabricated form. Importantly, the standard requires purchasers to specify the condition, finish and surface roughness of the base material because these affect the appearance and serviceability of the gold coating.

Key topics and technical requirements

• Designation and information to supplier: mandatory data the purchaser must provide (e.g., designation, significant surfaces, base‑metal condition, thickness/measurement locations, porosity and adhesion requirements).
• Coating composition and structure: single, double‑layer and multilayer gold/gold‑alloy coatings including specified alloying elements.
• Thickness measurement: methods and requirements for coating thickness (see Annex B and referenced ISO thickness standards).
• Porosity and corrosion testing: porosity tests, mixed‑flowing‑gas (MFG) environmental tests and accelerated‑corrosion methods.
• Adhesion and mechanical properties: adhesion tests (Annex C), microhardness, ductility and wear resistance.
• Electrical and soldering properties: contact resistance, solderability and relevant test procedures (references to IEC/ISO test methods).
• Undercoats and pre/post treatments: requirements for undercoat metals and heat treatments to control hydrogen embrittlement and stress relief (Annex A).
• Sampling and inspection: sampling procedures and acceptance criteria for production inspection (ISO 4519 referenced).

Practical applications and who uses ISO 27874

• Electroplating shops and surface‑finish suppliers use the standard to manufacture gold coatings that meet buyer specifications.
• Design engineers and OEMs specify coating type, thickness profile and areas requiring gold to balance performance and cost.
• Procurement and quality assurance teams include ISO 27874 references in purchase orders and inspection plans to ensure conformity.
• Test laboratories apply the standard’s test methods and normative references to verify porosity, thickness, adhesion, solderability and electrical properties.
  Typical applications include connectors, contacts, waveguides, PCB finish areas and wear‑resistant gold surfaces in electronics.

Related standards (selected)

• ISO 2064, ISO 1463, ISO 2177 (thickness measurement methods)
• ISO 4516 (microhardness), ISO 4519 (sampling)
• ISO 4524 series (gold coating test methods), ISO 14647 (porosity tests)
• IEC 60068-2-20 (solderability testing)

Keywords: ISO 27874, electrodeposited gold, gold alloy coatings, coating thickness, porosity testing, adhesion, solderability, electrical contact resistance.