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ISO 21968:2019 Non-magnetic metallic coatings on metallic and non-metallic basis materials - Measurement of coating thickness - Phase-sensitive eddy-current method >
ISO 21968:2019 Non-magnetic metallic coatings on metallic and non-metallic basis materials - Measurement of coating thickness - Phase-sensitive eddy-current method, 2019
- Foreword
- 1 Scope
- 2 Normative references
- 3 Terms and definitions
- 4 Principle of measurement
- 5 Factors affecting measurement uncertainty
- 5.1 Basic influence of the coating thickness
- 5.2 Electrical properties of the coating
- 5.3 Geometry — Base material thickness
- 5.4 Geometry — Edge effects
- 5.5 Geometry — Surface curvature
- 5.6 Surface roughness
- 5.7 Lift-off effect
- 5.8 Probe pressure
- 5.9 Probe tilt
- 5.10 Temperature effects
- 5.11 Intermediate coatings
- 5.12 External electromagnetic fields
- 6 Calibration and adjustment of the instrument
- 6.1 General
- 6.2 Thickness reference standards
- 6.3 Methods of adjustment
- 7 Measurement procedure and evaluation
- 7.1 General
- 7.2 Number of measurements and evaluation
- 8 Uncertainty of the results
- 8.1 General remarks
- 8.2 Uncertainty of the calibration of the instrument
- 8.3 Stochastic errors
- 8.4 Uncertainties caused by factors summarized in Clause 5
- 8.5 Combined uncertainty, expanded uncertainty and final result
- 9 Precision
- 9.1 General
- 9.2 Repeatability (r)
- 9.3 Reproducibility limit (R)
- 10 Test report
- Annex A (informative) Eddy-current generation in a metallic conductor
- Annex B (informative) Basics of the determination of the uncertainty of a measurement of the used measurement method corresponding to ISO/IEC Guide 98-3
- Annex C (informative) Basic performance requirements for coating thickness gauges based on the phase-sensitive eddy-current method described in this document
- Annex D (informative) Examples for the experimental estimation of factors affecting the measurement accuracy
- Annex E (informative) Table of the student factor
- Annex F (informative) Example of uncertainty estimation
- Annex G (informative) Details on precision
- Bibliography [Go to Page]