ISO 10309-1994 PDF

Full title and description

ISO 10309:1994 — Metallic coatings — Porosity tests — Ferroxyl test. International standard that specifies the ferroxyl (iron‑reagent) method for detecting pores and other discontinuities in metallic coatings, particularly for coatings that are cathodic to iron/steel and not visibly affected by ferricyanide and chloride ions during the test period.

Abstract

This standard defines a quick qualitative porosity test (the ferroxyl or iron‑reagent test) used to reveal pores, pinholes or discontinuities in metallic coatings. The method relies on migration of ions from the substrate through defects in the coating onto an indicator medium; exposure to a ferricyanide‑based indicator produces visible marks where the substrate metal is exposed or where electrochemical cells are active. The procedure is especially useful for thick, hard chromium coatings applied for wear resistance.

General information

• Status: Published (International Standard; confirmed on periodic review).
• Publication date: December 1994 (Edition 1, 1994-12).
• Publisher: International Organization for Standardization (ISO).
• ICS / categories: 25.220.40 — Metallic coatings; testing and inspection of coatings.
• Edition / version: Edition 1 (1994).
• Number of pages: 3 (original ISO publication).

Scope

ISO 10309:1994 specifies a laboratory method for revealing pores and other discontinuities in metallic coatings that are cathodic to iron or steel and that do not show visible reaction with ferricyanide and chloride ions during the test period. The standard covers the principle of the test, required materials and reagents, specimen and indicator paper preparation, the step‑by‑step procedure, criteria for observation and interpretation of test results, and notes on limitations and applicability (for example, its particular suitability for thick hard chromium coatings used for wear resistance).

Key topics and requirements

• Test principle: migration of substrate ions through coating defects and indication by a ferricyanide‑based reagent on an indicator medium.
• Reagents and materials: preparation and use of the ferricyanide (iron‑reagent) indicator solution and test paper or indicator medium.
• Specimen and indicator preparation: cleaning, mounting and arrangement of specimen and indicator paper to ensure reproducible contact.
• Procedure: application of reagent, exposure time, environmental considerations and stepwise actions required to develop and observe indications.
• Interpretation and reporting: identifying and recording the presence, distribution and relative severity of porosity (appearance of coloured/blue marks) and recommended reporting format.
• Limitations and applicability: coatings or substrate combinations for which the method is not suitable and factors that can affect sensitivity and reliability.
• Safety and handling: safe handling and disposal of chemical reagents and used indicator materials (use of PPE and good laboratory practice).

Typical use and users

Used by metallurgical and corrosion laboratories, plating and surface‑treatment manufacturers, quality assurance/quality control teams, inspection bodies and R&D groups working on metallic coatings. Typical applications include production control of electroplated and conversion coatings, investigation of coating failures, and verification of coating integrity where porosity can compromise corrosion protection or performance (for example, chromium wear coatings on steel parts).

Related standards

Standards and documents commonly referenced alongside ISO 10309 include EN ISO adoptions (EN ISO 10309:2016 — identical European adoption), and other porosity and coating test standards such as ISO 10308 (review/overview of porosity tests), ISO 15721 (porosity testing methods for specific noble metal coatings), ISO 6158 (related chromium coating practice), and various national adoptions and translations of ISO 10309.

Keywords

Ferroxyl test, iron reagent test, porosity test, metallic coatings, pinhole detection, chromium coatings, plating inspection, coating integrity, substrate porosity, ICS 25.220.40.

FAQ

Q: What is this standard?

A: ISO 10309:1994 is an International Standard that specifies the ferroxyl (iron‑reagent) porosity test method for detecting pores and discontinuities in metallic coatings.

Q: What does it cover?

A: It covers the principle of the ferroxyl porosity test, required reagents and materials, specimen and indicator preparation, the stepwise test procedure, observation and interpretation of indications, reporting recommendations, and notes on limitations and safety.

Q: Who typically uses it?

A: Plating and surface‑treatment manufacturers, corrosion and metallurgical test labs, quality control/inspection personnel, and researchers evaluating coating porosity and protective performance.

Q: Is it current or superseded?

A: The ISO publication is the 1994 first edition. The ISO record shows the standard has been subject to periodic review and was confirmed on review cycles (the ISO bibliographic record lists confirmation on review). The text has been adopted identically in some regional/national collections (for example EN ISO 10309:2016). No later ISO edition replacing the 1994 international text is identified in the ISO bibliographic record.

Q: Is it part of a series?

A: It is one of several international standards and technical reports addressing porosity and porosity test methods for metallic coatings (see related documents such as ISO 10308, ISO 15721 and other porosity‑testing standards and reviews).

Q: What are the key keywords?

A: Ferroxyl test, porosity, pinholes, metallic coatings, plating inspection, iron reagent, coating integrity.