Overview
ISO 15208:2022 - "Continuous hot-dip zinc-coated twin-roll cast steel sheet of commercial quality" - specifies requirements for steel sheet produced by the continuous hot‑dip zinc coating process applied to twin‑roll cast strip. It covers products supplied in coils and cut lengths, intended for applications needing corrosion resistance, formability and paintability. The standard defines grades, coating masses, surface finishes and ordering conditions for commercial‑quality twin‑roll cast zinc‑coated steel.
Key topics and technical requirements
- Dimensions and product form
- Sheet thicknesses up to 2.0 mm (after coating) and widths up to 2 000 mm; sheets less than 600 mm slit from wide sheet treated as sheet.
- Thickness may be specified as base‑metal only or base‑metal plus coating (purchaser must state preference).
- Manufacture and chemical control
- Requirements for steelmaking, chemical composition and both heat and product analyses.
- Mechanical properties and testing
- Tensile testing (room temperature) and bend tests referenced; sampling and retest provisions defined.
- Coating requirements
- Coating mass expressed in g/m2 (total both surfaces), coating adherence and use of differential coatings (different masses on each side).
- Surface finishes: normal spangle, minimized spangle, and skin pass options.
- Surface treatments and paintability
- Mill passivation, mill phosphating and oiling requirements to support painting and forming.
- Weldability and coated coil joining
- Guidance on suitability for welding and methods to join coated coils.
- Dimensional and shape tolerances, inspection and acceptance
- Sampling methods, test methods and designation/marking systems; provisions for workmanship, retests and resubmission.
Practical applications and users
ISO 15208:2022 is used by:
- Steel producers and continuous coating line operators to specify production, coating mass and surface finish.
- Purchasers, specifiers and procurement teams in construction, automotive components, white goods, roofing and general industrial fabrication who need corrosion‑resistant, formable, paintable sheet.
- Fabricators and paintshops requiring defined surface pretreatments (phosphating, passivation) and formability/weldability data.
- Quality, testing and inspection laboratories for sampling, tensile and coating tests to verify compliance.
Typical applications include painted panels, formed components, exterior cladding, appliance housings and other moderately formed or flat-sheet uses where durability and paint adhesion are important.
Related standards
ISO 15208 references several normative standards for tests and measurements, including:
For specification, procurement or compliance, consult the full ISO 15208:2022 document and the referenced ISO test standards for complete technical details.