ISO 7599:2018

Overview - ISO 7599:2018 (Anodizing of aluminium and its alloys)

ISO 7599:2018 defines a standardized method for specifying decorative and protective anodic oxidation coatings on aluminium (including aluminium-based alloys). It describes the characteristic properties of anodic coatings, lists test methods to verify those properties, sets minimum performance requirements, and gives guidance on suitable aluminium grades and the role of pretreatment for achieving the required appearance or texture.

The standard is focused on porous anodic coatings used for aesthetic and protective finishes. It explicitly excludes barrier-type non-porous coatings, chromic/phosphoric acid anodizing processes, coatings intended only as a base for organic coatings or metal electrodeposition, and hard anodic coatings where wear resistance is the primary requirement.

Key technical topics and requirements

• Characteristic properties: Defines attributes to specify for anodic oxidation coatings such as thickness, appearance, colour, corrosion resistance, abrasion/wear resistance, resistance to cracking by deformation, lightfastness and electrical breakdown potential.
• Testing and acceptance: Lists standardized test methods and procedures for sampling, acceptance, referee and production control testing (see clauses on tests, sampling and test specimens).
• Coating thickness: Classification and measurement methods for coating thickness, including non‑destructive and microscopical techniques.
• Sealing quality: Assessment methods for hydrothermal and cold sealing, and guidance on other sealing treatments to control absorptive power and durability.
• Appearance and colour control: Guidance on visible defects, colour and surface texture specification and production control checks.
• Corrosion and wear: Methods for assessing corrosion resistance (salt spray, pitting evaluation) and abrasion/wear testing.
• Other measurements: Continuity checks, mass per unit area, light reflection and image clarity, and electrical breakdown potential.
• Customer-supplied information: Essential items customers must provide to anodizers - intended service, aluminium specification, significant surfaces, surface preparation, required thickness class, clear or coloured finish, and sealing requirements.

Practical applications and users

ISO 7599:2018 is used by:

• Anodizing service providers and coating process engineers to define, control and certify anodic finishes.
• Product designers, OEMs and specifiers who require durable decorative or protective aluminium surfaces (architectural panels, consumer goods, trim, enclosures).
• Quality managers and inspectors for production control, acceptance testing and dispute resolution.
• Material engineers and procurement teams to select suitable aluminium grades and pretreatment processes.

By following ISO 7599:2018, stakeholders ensure consistent aesthetic quality, predictable corrosion and wear performance, and clear contractual specifications for anodized aluminium components.

Related standards

Relevant ISO documents referenced include standards for thickness measurement (ISO 1463, ISO 2128), continuity checks (ISO 2085), mass per unit area (ISO 2106), sealing and corrosion assessment (ISO 2143, ISO 2931, ISO 3210), abrasion (ISO 8251), and terms/definitions (ISO 7583). For hard anodic coatings see ISO 10074.