Overview
ISO 8353:2024 specifies minimum requirements for steel sheet (in coils and cut lengths) that is zinc‑aluminium‑magnesium (Zn‑Al‑Mg) alloy coated by the continuous hot‑dip process. The standard covers steel of commercial, drawing and structural qualities intended for applications that require high corrosion resistance, good formability and paintability. It defines product designations, coating types and masses, surface treatments and finish conditions to ensure compatibility with diverse application needs.
Key Topics
- Scope and product forms - Coils and cut lengths of hot‑dip Zn‑Al‑Mg alloy‑coated steel sheet for multiple base‑metal quality classes (commercial, drawing, structural).
- Conditions of manufacture - Requirements for steelmaking, chemical composition, and mechanical properties for different quality designations.
- Coating requirements - Specification of coating type designations, coating bath composition, coating mass and coating adherence (no numeric bath composition or mass values are reproduced here).
- Surface treatments and finish - Mill passivation, mill phosphating, oiling and thin organic films (sealing) plus coating finish conditions to support painting and forming operations.
- Weldability and painting - Requirements and guidance related to joining, welding and paintability of coated products.
- Dimensional, shape and coil tolerances - Defined tolerances for thickness, width, length and coil geometry to ISO tolerancing practices.
- Sampling, testing and inspection - Sampling plans and tests including tensile testing, coating mass measurement, coating‑adhesion tests (single‑spot, triple‑spot), and corrosion testing methods referenced to established ISO test methods.
- Designation, marking and purchaser information - A system for product designation (including coating type, mass and finish), marking rules and the information the purchaser must supply.
Applications
ISO 8353 targets industries and stakeholders that require durable, formable, paintable coated steel:
- Automotive body panels and components requiring corrosion protection and deep‑drawing capability
- Building and construction elements (cladding, roofs, façades) exposed to corrosive environments
- White goods and appliances where paintability and appearance matter
- General fabrication and structural components needing improved corrosion resistance
- Steel producers, coating line operators, specifiers, purchasing agents, quality labs and testing houses involved in material qualification and acceptance
Related Standards
Key normative references used by ISO 8353 for test and measurement methods include:
ISO 8353:2024 provides a practical framework for specifying and verifying hot‑dip Zn‑Al‑Mg alloy‑coated steel sheet, helping manufacturers and buyers ensure consistent performance in corrosion‑sensitive, formed and painted applications.