Selection summary
Overview
Z275 under EN 10346 specifies a minimum 275 g/m² total zinc coating mass on both sides of continuously hot-dip coated flat product. The designation belongs inside an EN order with its substrate grade, surface quality, treatment and inspection rules; the mass number alone does not prove full equivalence to an ASTM product.
This page separates standard-oriented limits from typical reference data. Purchase acceptance comes from the ordered specification and certified material test report.
Names and systems
Identity & standards
Similar designations across ASTM, EN, JIS, and other systems are not automatically interchangeable. Product form and ordered standard control chemistry, properties, dimensions, condition, and testing.
Reference chemistry
Composition
| Element | Reference range | Why it matters |
|---|---|---|
| Zinc coating | Designation-system controlled | Atmospheric corrosion protection for the coated sheet system |
| Steel substrate | Ordered separately | Carries strength, formability and dimensional requirements |
Concise grade-family reference only. Confirm every element limit against the current standard for the exact product ordered.
Condition matters
Reference properties
A designation is meaningful only with its governing standard, edition and product form.
Typical web values are screening information, not purchase acceptance limits.
Environment first
Corrosion behavior
Coating life depends on coating system, exposure, drainage, cut edges, fabrication damage and maintenance.
A coating designation does not establish universal service life or suitability.
Temperature, concentration, deposits, crevices, stress, surface finish, cleaning, and fabrication quality can change service performance.
Service limits
Temperature & service
Confirm temperature limits through the governing design code, product standard and complete material system.
Delivery condition
Heat treatment & condition
Do not infer heat treatment or temper from an incomplete designation.
State the ordered condition or temper and verify it on the certificate.
Process route
Fabrication
Qualify forming, welding, joining and surface-repair procedures for the ordered product form.
Preserve material or coating traceability after cutting and secondary processing.
Magnetic response: The steel substrate is ferromagnetic.
Decision boundaries
Comparisons & substitution
Published coating tables place ASTM G90 and Z275 on a closely corresponding total-mass basis, not as universally interchangeable finished products.
Unlike G60 and G90 inch-pound names, Z275 states the nominal SI mass designation directly; retain EN 10346 acceptance language when it governs.
Where it is used
Applications
Ordering scope
Product forms & standards
Continuously galvanized EN flat product; not an after-fabrication galvanizing specification
Decision support
Selection guidance
Choose this grade when
- The contract uses EN 10346 and explicitly specifies Z275 with a compatible substrate designation.
- Surface quality, surface treatment, dimensional tolerances and downstream forming or painting are written into the order.
Review another grade when
- An ASTM or JIS contract is being converted without agreement on test method, substrate grade and certificate wording.
- Aggressive exposure, cut edges, welds or contact with dissimilar materials governs durability.
Before ordering
Procurement checklist
State the coating standard, ordered edition and exact coating designation.
State substrate grade, delivery condition, thickness, width, tolerances and quantity.
State surface treatment, oil/passivation, spangle, intended forming and cut-edge controls.
Require coating evidence, substrate certificate, coil traceability, marking and dry export packing.
Retain EN 10346 substrate, surface-quality and treatment suffixes; verify the certificate reports Z275 and the governing coating-mass assessment.
Traceable evidence