ISO 2360:2017 PDF

Overview

ISO 2360:2017 specifies a non-destructive, amplitude-sensitive eddy-current method for measuring the thickness of non-conductive coatings on non‑magnetic electrically conductive base metals. Typical coatings include paints, varnishes, anodic oxide films, electroplated and powder coatings, enamels and plastic claddings. The standard describes measurement principles, calibration, sources of error and uncertainty, precision and test reporting for reliable coating thickness measurement using amplitude-sensitive eddy-current instruments.

Key topics and technical requirements

• Principle of measurement: probe-generated high-frequency electromagnetic field induces eddy currents in the conductive base; changes in probe coil impedance amplitude (resonant frequency shift) are calibrated to coating thickness.
• Calibration & adjustment: requirements for using appropriate thickness reference standards and methods for instrument adjustment and calibration to obtain traceable results.
• Factors affecting uncertainty: detailed treatment of influences such as
  • coating thickness range and probe sensitivity,
  • electrical conductivity of the base metal,
  • base metal thickness, edge effects and surface curvature,
  • surface roughness and cleanliness (lift-off),
  • probe pressure and tilt,
  • temperature and external electromagnetic fields,
  • intermediate coatings and inhomogeneities.
• Measurement procedure & evaluation: recommended measurement practices, number of readings, statistical evaluation and reporting.
• Uncertainty & precision: guidance on estimating combined and expanded uncertainty, repeatability (r) and reproducibility (R).
• Informative annexes: background on eddy-current generation, uncertainty estimation (GUM), performance requirements for gauges, experimental examples and precision details.

Practical applications and users

ISO 2360:2017 is used for quality control, acceptance testing and process monitoring where fast, non-destructive coating thickness checks are required. Typical users:

• QA/QC engineers and production inspectors in automotive, aerospace, marine and general metal finishing industries.
• Anodizing and plating shops validating oxide layers and non-conductive coatings.
• Third‑party testing laboratories and NDT technicians performing routine coating surveys.
• Coating manufacturers and applicators ensuring specification compliance.

Notes on applicability:

• Particularly suited to anodized oxide coatings; not suitable for some extremely thin conversion coatings.
• Can measure non‑magnetic metallic coatings on non‑conductive substrates, but ISO 21968 (phase-sensitive eddy-current) often gives higher accuracy.
• Not recommended for coatings on magnetic base metals (see ISO 2178), except for very thick coatings (≈1 mm) where amplitude-sensitive methods may be used.

Related standards

• ISO 21968 - Phase-sensitive eddy-current thickness measurement
• ISO 2178 - Magnetic method for non-magnetic coatings on magnetic substrates
• ISO 2064, ISO 4618, ISO/IEC Guide 98-3 (GUM) - terminology and uncertainty guidance

Keywords: ISO 2360:2017, coating thickness measurement, eddy-current, amplitude-sensitive, non-destructive testing, anodizing, calibration, measurement uncertainty.