ISO 10111:2019

Overview

ISO 10111:2019 provides guidelines for determining the mass per unit area (surface density) of metallic and other inorganic coatings using gravimetric and chemical analysis methods. The standard covers coatings such as anodic oxide, autocatalytic deposits, chemical conversion layers, electrodeposits, hot-dip galvanizing, and coatings from chemical or physical vapour deposition. Methods include dissolving the coating or substrate, weighing before/after processes, and instrumental chemical analysis of resulting solutions.

Key topics and technical requirements

• Measurement principle: surface density is derived from measured mass and area; thickness can be calculated from mass, area and coating density.
• Approved methods:
  • Gravimetric dissolution of the coating or substrate (chemical or electrochemical).
  • Gravimetric difference weighing (uncoated substrate vs finished specimen).
  • Chemical analysis of dissolved coating using instrumental techniques (e.g., photometric, volumetric, AAS, ICP).
• Specimen preparation: recommendations on specimen size, shape (rectangular/circular preferred), edge dressing and optional heat treatment to maintain coating integrity during substrate dissolution.
• Area measurement: use of planimeter, calipers, measuring microscope; for improved accuracy consider accounting for surface roughness using AFM, confocal or interference microscopy to determine relative surface area increase (RSAI).
• Procedural variants: difference methods, direct weighing after substrate dissolution, difference without dissolution - each described with applicable restrictions and equipment needs.
• Annex A (informative): examples of reagents for selective dissolution; users may apply other suitable solutions.
• Limitations: chemical methods are unsuitable when coating and substrate cannot be chemically separated or share inseparable constituents (e.g., certain alloys). Measurement uncertainties are not provided in this document except where referenced to ISO 3892.
• Safety note: use can involve hazardous chemicals and equipment; follow appropriate safety and environmental controls.

Practical applications and users

ISO 10111:2019 is intended for:

• Quality control and testing laboratories measuring coating mass per unit area and deriving coating thickness.
• Surface engineers, plating and galvanizing operations, metallurgists and R&D teams developing or validating coating processes.
• Procurement/specification writers and conformity assessors who require standardized procedures for coating mass/area measurement.

Use cases:

• Verifying plating thickness requirements by converting surface density to thickness.
• Comparing coating mass across production batches.
• Establishing traceable test methods for inspection and acceptance of protective or decorative coatings.

Related standards

• ISO 3892 - referenced gravimetric method with measurement uncertainty guidance.
• ISO 2080 - vocabulary for metallic and other inorganic coatings.
• Prepared by ISO/TC 107 (Metallic and other inorganic coatings).

Keywords: ISO 10111:2019, mass per unit area, metallic coatings measurement, gravimetric methods, chemical analysis, surface density, coating thickness, anodic oxide, hot dip galvanizing.