Overview
ISO 24417:2022 specifies a glow-discharge optical emission spectrometry (GD-OES / glow-discharge OES) method for the quantitative analysis of metallic nanolayers on iron‑based substrates. It covers determination of thickness and mass per unit area (areic mass) for single and multilayer metallic coatings 10 nm to 100 nm thick. The method is applicable to layers containing Cr, Ni, Ti, Mn, Al and also allows determination of P and S where relevant.
Key topics and technical requirements
- Analytical principle: Continuous cathodic sputtering of the coating in a DC or RF glow‑discharge source, excitation of atoms in the plasma and time‑resolved spectrometric measurement to produce depth profiles (intensity vs. time) converted to mass fraction vs. depth via calibration.
- Applicable thickness range: 10–100 nm nanolayers on iron‑based substrates.
- Analyte elements: Primary: Cr, Ni, Ti, Mn, Al. Additional: P, S.
- Instrumentation: Grimm‑type (or similar) glow discharge source coupled with a simultaneous optical emission spectrometer. Recommended hollow anode inner diameter: 2–8 mm. Cooling for thin specimens is recommended.
- Source modes: DC or RF-powered glow discharge; pulsed modes are noted as beneficial for heat‑sensitive samples.
- Data acquisition: For nanolayer analysis, systems capable of at least 100 measurements/second per spectral channel are recommended to resolve thin layers.
- Spectral line selection: Choose lines based on spectral range, sensitivity, self‑absorption risks and spectral interferences. Annex B provides suggested lines.
- Calibration & validation: Use calibration samples with known composition and measured sputtering rate; perform validation with reference materials; account for drift and lamp cleanliness.
- Performance criteria: Requirements include repeatability, detection limits and verification procedures (see clauses on minimum performance and precision).
- Reporting: The standard details required reporting elements for traceable test results.
Applications and users
ISO 24417 is aimed at laboratories and organizations performing surface chemical analysis and coating characterization where ultrathin metallic layers on iron‑based substrates need quantification. Typical users:
- Coating and surface analysis laboratories (quality control and R&D)
- Manufacturers of plated or PVD/CVD coated steel components (automotive, tooling, corrosion protection)
- Materials scientists studying nanocoatings and thin‑film metallurgy
- Certification bodies and test houses requiring standardized GD‑OES methods
Practical uses include verification of coating thickness/mass, production control, failure analysis and comparative testing of surface treatments.
Related standards
- ISO 14707 - Glow discharge optical emission spectrometry (GD‑OES) - Introduction to use
- ISO 14284 - Steel and iron - Sampling and preparation for chemical composition
Keywords: ISO 24417, GD‑OES, glow‑discharge optical emission spectrometry, metallic nanolayers, iron‑based substrates, coating thickness, areic mass, Cr Ni Ti Mn Al, depth profile, calibration, sputtering rate.