ZM is a Zn-Al-Mg (zinc-aluminum-magnesium) coated steel as defined in EN 10346 standard. It is applied by a continuous hot-dip process; the bath composition is Al+Mg total %1.5–8 and Mg minimum %0.2.

ZM Coated Steel (Zn-Al-Mg) Technology

Q: Are Magnelis and PosMAC the same thing?

No. Magnelis (Zn-3,5Al-3Mg) is a registered trademark of ArcelorMittal, and PosMAC (Zn-3Mg-2,5Al) is a registered trademark of POSCO. Both are in the EN 10346 ZM class but have brand-specific performance and warranty profiles.

Q: What is the difference between HDG and ZM?

HDG immerses the part in a zinc bath after production; ZM applies a continuous Zn-Al-Mg coating during production. The biggest difference of ZM is self-repair at the cut edge: post-cutting Zn-Al-Mg ions passivate the surface.

Q: How long will ZM coating last?

It depends on the atmospheric environment class. According to ArcelorMittal publication for ZM430: C2 >50 years, C3 40–50 years, C4 20–40 years, C5 10–20 years. These values are the indicator's design life and should not be confused with the warranty period.

Q: What standards does ZM coated steel comply with?

The main reference is EN 10346:2015 (TS EN 10346). ISO 8353:2024, published at the end of 2024, is a specific international product standard for ZM coated steel. Document level EN 10204 Type 3.1 is mandatory.

Güneş tarlaları 25 yıl yaşar — altındaki çelik de yaşamalı. ZM kaplamalı çelik (Zn-Al-Mg) kesilmiş kenarda kendini onarır, HDG'ye göre yarı kalınlıkta 2× daha uzun dayanım verir. Magnelis® & PosMAC® ürün aileleri — EN 10346 ve ISO 8353:2024 standartlarında sertifikalı tedarik.

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Summary

Why ZM?

50µm İnce ama güçlü

ZM620 tek yüz kaplama — HDG'ye göre 2× daha az malzeme, daha uzun ömür.
>50yıl Saha ömrü

C2 / C3 sınıfında ZM430 — ArcelorMittal Magnelis® tasarım verisi.
10× Kenar koruma

Kesilmiş kenarda öz-onarım — HDG'nin yapamadığı benzersiz özellik.
EN 10346 Standard

ZM310 / ZM430 sınıfları + S350GD–S450GD çelik. ISO 8353:2024 uyumlu.

Dictionary

ZM, Magnelis®, PosMAC®, HDG — they are not the same thing.

Within the scope of EN 10346 general Zn-Al-Mg coating family. Brand-independent technical grade. Al+Mg total %1.5–8, Mg ≥ %0.2.

Magnelis®

ArcelorMittal'Trademark of [Company Name]. Bathroom chemistry Zn-%3,5Al-%3Mg. Brand solution within the ZM class.

PosMAC® 3.0

POSCO'Trademark of [Company Name]. Bathroom chemical Zn-%3Mg-%2,5Al. ISOTEC 3.1 certified supply line.

HDG

Hot-dip galvanizing. After manufacturing, the part is immersed in the bath; from ZM. different Process and strength profile.

Terminology details →

Design life

How durable is ZM in C1–C5 corrosion classes?

Corrosion Class

ZM310 ZM430 ZM620^*

Corrosion Class	ZM310	ZM430	ZM620*
C2 Kırsal / düşük kirletici	>50	>50	>50
C3 Şehir / orta kirletici	30–50	40–50	>50
C4 Endüstriyel / orta tuz	15–30	20–40	30–50
C5 Yüksek tuz / agresif	8–15	10–20	15–30

^* ZM620 EN 10346:2015'te yer almaz; üretici teknik yayını verisidir. Kaynak: ArcelorMittal Magnelis® teknik yayını. Notes: Design lifespan ≠ Warranty period.

Corrosion details + interactive map of Türkiye →

Accredited test

Which lab is accredited for ZM? Quick search.

Lab search engine (mini mode) — to be loaded in UI Plan 03 (Lab data + UI).

Currently, 1 lab is registered in the database.

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Technology ecosystem — 6 topics

Terminology

ZM, Magnelis®, PosMAC®, HDG — which is a brand, which is a class? How should purchasing language be written?

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Standards & Tests

EN 10346, ISO 8353:2024, EN 10204 Type 3.1 — specification and verification methods (XRF, OES, ISO 9227).

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Corrosion Resistance

Design life cycle tables for C1–C5 classes. Interactive Türkiye/Europe map (on the details page).

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Accredited Laboratories

TR + global ISO/IEC 17025 accredited labs. Search engine with method + country + accreditation filters.

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HDG vs ZM

Hot-dip galvanizing versus ZM coating — cut edge, design life, cost, which project has which?

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Documents

The customer brochure, 5 technical reports, and technical specifications are all available for direct download. The contractual text will be added upon request.

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Technical library

Brochure, specifications, 5 technical reports

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Customer Brochure A3

ZM Magnelis® / PosMAC® promotional and sales materials, PDF available with a single click.

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Report 1 — Terminology

The technical distinction between ZM and Magnelis/PosMAC is defined within the framework of EN 10346.

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Report 2 — Specification & Testing

Procurement specifications, incoming quality control plan, testing methods.

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Report 3 — C1–C5 Corrosion

Design lifecycle tables, reading warranty information, practical field recommendations.

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Report 4 — Accredited Laboratories

TR + global ISO 17025 lab map, method scopes.

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Report 5 — HDG vs ZM

Coating system comparison, project-based selection criteria.

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🔴 Upon request

Ground-mounted Solar Power Plant Technical Specifications

Contractual document — for offer/order/contract stages.

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All documents →

Frequently Asked Questions

10 short answer questions

What is ZM coating?

ZM is a Zn-Al-Mg (zinc-aluminum-magnesium) coated steel as defined in EN 10346. It is applied by a continuous hot-dip process; the bath composition is a total Al+Mg ratio of %1.5–8 and a minimum Mg ratio of %0.2. It offers a different process and performance profile than conventional hot-dip galvanizing (HDG).

Are Magnelis® and PosMAC® the same thing?

No. They are both in the ZM class, but from different brands: Magnelis® is ArcelorMittal's (Zn-%3,5Al-%3Mg) and PosMAC® is POSCO's (Zn-%3Mg-%2,5Al) registered trademark. EN 10346 ZM class covers both brands, but the warranty, field resistance, and some test results are manufacturer-specific and cannot be automatically transferred between them.

What is the difference between ZM310 and ZM430?

The number represents the total coating mass (g/m²). ZM310 = 310 g/m², single surface approximately 24 µm. ZM430 = 430 g/m², single surface approximately 35 µm. Thicker coating with ZM430 = longer atmospheric design lifetime. ZM430 is the corporate base choice for medium-to-heavy environmental classes (C3–C4).

What is the difference between HDG and ZM?

HDG (Hot-Dip Galvanizing) immerses the part in a zinc bath after production; ZM, on the other hand, applies a continuous Zn-Al-Mg coating during production. The biggest difference of ZM is... self-repair on cut edgeThe area opened by the cutting self-passivates with Zn-Al-Mg ions. HDG is unprotected at the cut edge and requires additional repair.

What standards does ZM coated steel comply with?

Main normative reference EN 10346:2015''It is equivalent to TS EN 10346. Steel grade S350GD / S420GD / S450GD, coating grade ZM310 / ZM430 are defined in this standard. Published at the end of 2024. ISO 8353:2024 ZM is a specific international product standard for coated steel. The mandatory certification level is EN 10204 Type 3.1.

How long will ZM coating last?

It depends on the atmospheric environmental class. According to ArcelorMittal Magnelis® publication, for ZM430: C2 >50 years, C3 40–50 years, C4 20–40 years, C5 10–20 years. These are indicator design lifeThis is not a warranty period. The warranty varies depending on the brand, environment, and installation details. See the corrosion cluster page for details.

Why is ZM preferred for solar panel carriers?

In solar power plant sites, profiles are cut or drilled using lasers/plasma/shears. HDG, on the other hand, only protects the part surface; the cut edge remains exposed. ZM's edge self-healing behavior is critical for its 25+ year field life. Furthermore, ZM can be applied to thin-section profiles, and HDG has no post-process immersion limitations.

Which ZM product does ISOTEC supply?

Our current 3.1 certified supply line comes from POSCO PosMAC® 3.0 (Zn-%3Mg-%2,5Al) products. Project-based Magnelis® supply is also possible. Specification language can be brand-independent (EN 10346 ZM) or brand-specific (e.g., Magnelis® or equivalent); brand-specific performance claims are documented by the relevant manufacturer publication.

How is ZM coated steel tested?

For routine incoming inspection: 3.1 certification + visual surface + XRF thickness. In case of arbitration, EN 10346 Annex A coating mass stripping test. Base steel chemistry is verified by OES (ASTM E415), coating thickness by XRF/ISO 3497, and corrosion by ISO 9227 salt spray. See "Accredited Laboratories" page for the list of accredited labs.

Is ZM sufficient for elements in contact with soil or concrete?

Atmospheric design life table (C1–C5) does not cover continuous moisture, soil contact, or embedded use in concrete. Separate field data and manufacturer-specific verification are required under these conditions. In critical contact areas, ZM430/ZM620 + insulation detail + alternatively, a duplex (ZM + paint) system is considered.

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ZM Coated Steel (Zn-Al-Mg) Technology

Why ZM?

ZM, Magnelis®, PosMAC®, HDG — they are not the same thing.

How durable is ZM in C1–C5 corrosion classes?

Which lab is accredited for ZM? Quick search.

Technology ecosystem — 6 topics

Brochure, specifications, 5 technical reports

10 short answer questions

Get a project-specific quote for a ZM coated solution.

ISOTEC Türkiye – Factory

ISOTEC Germany

Menu

Quality Certificates

ZM Coated Steel (Zn-Al-Mg) Technology

Why ZM?

ZM, Magnelis®, PosMAC®, HDG — they are not the same thing.

How durable is ZM in C1–C5 corrosion classes?

Which lab is accredited for ZM? Quick search.

Technology ecosystem — 6 topics

Brochure, specifications, 5 technical reports

10 short answer questions

Get a project-specific quote for a ZM coated solution.

ISOTEC Türkiye – Factory

ISOTEC Germany

Menu

Quality Certificates

Erkan Öztürk