EN ISO 4518:2021 PDF

Overview

EN ISO 4518:2021 (ISO 4518:2021) specifies the profilometric method for measurement of metallic coating thickness. The procedure forms a step between coating and substrate (by dissolving part of the coating or by masking prior to coating) and determines thickness by measuring the step height with a profile-recording instrument. The method applies to coatings from 0,01 µm to 1 000 µm on flat surfaces and, with precautions, on cylindrical surfaces. It is particularly suitable for minute thicknesses and for preparing coating thickness reference standards.

Keywords: EN ISO 4518:2021, ISO 4518:2021, profilometric method, metallic coatings, coating thickness measurement, profilometer.

Key Topics

• Principle: Create a step (masked area or partial dissolution) then measure step height using a profilometer.
• Instrumentation:
  • Contact stylus instruments (surface analysers / profile recorders) - useful for roughness and step profile measurement.
  • Inductive measuring probes / displacement sensors - incremental or absolute sensors for profile recording.
  • Optical profilometers - white-light interference or confocal microscopes (including laser scanning/chromatic confocal) for non-contact profile measurement.
• Stylus specifics: Nominal tip radii commonly used include 2, 5, 10, 50 µm; the standard specifies maximum static forces for different tip sizes (see Table 1 in the document).
• Measurement range & limits: Applicable from 0,01 µm to 1 000 µm; not recommended below 0,01 µm because surface flatness and smoothness dominate uncertainty.
• Factors affecting accuracy: surface roughness, stylus diameter, applied force, vibrations, surface curvature, cleanliness, temperature, step configuration, datum reference and calibration.
• Procedure elements: preparation of the step, profile recording, thickness evaluation, measurement accuracy assessment and required test reporting.

Applications

• Quality control and acceptance testing of metal coatings (plating, electroplating, conversion coatings).
• Production inspection where masked areas are used to generate measurement steps.
• Metrological laboratories preparing or verifying coating thickness reference standards.
• Industries using precision thin films where sub-micron thickness measurement is required (automotive, electronics, corrosion protection, decorative finishes).

Who uses it: coating laboratories, quality engineers, metrology labs, materials scientists, and manufacturers of profilometric instruments.

Related Standards

• ISO 2177 - Metallic coatings - Measurement of coating thickness - Coulometric method by anodic dissolution (normative reference cited in EN ISO 4518:2021).

For implementation, consult the full EN ISO 4518:2021 text for detailed instrument specifications, tolerances, calibration methods and reporting requirements.