prEN 10346

Continuously hot-dip coated steel flat products for cold forming - Technical delivery conditions

This document specifies requirements for continuously hot-dip coated products made of low carbon steels for cold forming, of steels for construction and of steels with high proof strength for cold forming coated with zinc (Z), zinc-iron alloy (ZF), zinc-aluminium alloy (ZA), zinc-magnesium alloy (ZM), aluminium-silicon alloy (AS) or aluminium (A) and for continuously hot-dip coated products made of multiphase steels for cold forming coated with zinc (Z), zinc-iron alloy (ZF), zinc-aluminium alloy (ZA) or zinc-magnesium alloy (ZM) in thicknesses of 0,20 mm ≤ t ≤ 6,5 mm.
By agreement at the time of enquiry and order, this document is applicable to continuously hot-dip coated flat products of an expanded validity range defined for thicknesses t < 0,20 mm with agreed mechanical properties and test specimens, adhesion of coating and surface condition requirements. This document applies to strip of all widths and to sheets cut from it (≥600 mm width) and cut lengths (<600 mm width).
NOTE   The products covered by this document are used where cold formability, high strength, a defined minimum yield strength and/or corrosion resistance are the most important factors. Corrosion resistance of the product is depending on coating type and coating thickness, hence to its mass (see also 7.3.2). The products covered by this document can be used as substrates for organic coated flat products specified in EN 10169 for building and general engineering applications.

Kaltgewalzte kontinuierlich schmelztauchveredelte Flacherzeugnisse aus Stahl - Technische Lieferbedingungen

Dieses Dokument legt die Anforderungen an kontinuierlich schmelztauchveredelte Flacherzeugnisse aus weichen Stählen zum Kaltumformen, Stählen für die Anwendung im Bauwesen, Stählen mit hoher Dehngrenze zum Kaltumformen mit Überzügen aus Zink (Z), Zink Eisen Legierung (ZF), Zink Aluminium Legierung (ZA), Aluminium Zink Legierung (AZ) oder Aluminium Silicium Legierung (AS) sowie aus Mehrphasenstählen zum Kaltumformen mit Überzügen aus Zink (Z), Zink Eisen Legierung (ZF), Zink Aluminium Legierung (ZA) oder Zink Magnesium Legierung (ZM) in Dicken von 0,20 mm ≤ t ≤ 6,5 mm - falls nicht anders vereinbart - fest.
Nach Vereinbarung zum Zeitpunkt der Anfrage und Bestellung gilt dieses Dokument für kontinuierlich schmelztauchveredelte Flacherzeugnisse eines erweiterten Gültigkeitsbereichs, der für Dicken t <0,20 mm mit vereinbarten mechanischen Eigenschaften und Prüfmustern, Anforderungen an die Haftung der Beschichtung und die Oberflächenbeschaffenheit definiert ist. Dieses Dokument gilt für Bänder aller Breiten und für daraus geschnittene Bleche (≥600 mm Breite) und Schnittlängen (<600 mm Breite).
ANMERKUNG   Die in diesem Dokument behandelten Produkte werden dort eingesetzt, wo Kaltumformbarkeit, hohe Festigkeit, eine bestimmte Mindeststreckgrenze und/oder Korrosionsbeständigkeit die wichtigsten Merkmale sind. Die Korrosionsbeständigkeit des Erzeugnisses ist abhängig von der Art der Beschichtung und der Schichtdicke, also von seiner Masse (siehe auch 7.3.2). Die in diesem Dokument behandelten Produkte können als Trägermaterial für organisch beschichtete Flacherzeugnisse nach EN 10169 für Anwendungen im Bauwesen und im allgemeinen Maschinenbau verwendet werden.

Produits plats en acier revêtus en continu par immersion à chaud pour formage à froid - Conditions techniques de livraison

Le présent document spécifie les exigences relatives aux produits en acier revêtus en continu par immersion à chaud constitués d’aciers à bas carbone pour le formage à froid, d’aciers de construction, d’aciers à haute limite conventionnelle d’élasticité pour le formage à froid, et revêtus de zinc (Z), d’alliage zinc-fer (ZF), d’alliage zinc-aluminium (ZA), d’alliage zinc-magnésium (ZM), d’alliage aluminium-silicium (AS), ou d’aluminium (A) et aux produits galvanisés à chaud en continu constitués d'aciers multiphasés pour le formage à froid revêtus de zinc (Z), d’alliage zinc-fer (ZF), d’alliage zinc-aluminium (ZA) ou d’alliage zinc-magnésium (ZM) avec des épaisseurs de 0,20 mm ≤ t ≤ 6,5 mm.
Par accord au moment de l’appel d’offres et de la commande, le présent document est applicable aux produits plats revêtus en continu de domaines étendus de validité définis pour les épaisseurs t < 0,20 mm possédant des propriétés mécaniques et des éprouvettes, des conditions d’adhésion du revêtement et des exigences en matière d'état de surface. Le présent document s’applique aux bandes de toutes largeurs ainsi qu’aux tôles (largeur ≥ 600 mm) et aux bandes refendues coupées à la longueur (largeur < 600 mm) qui y sont découpées.
NOTE   Les produits couverts par le présent document sont utilisés lorsque le formage à froid, une résistance élevée, une limite apparente d’élasticité minimale définie et/ou une résistance à la corrosion sont les facteurs les plus importants. La résistance du produit à la corrosion dépend du type et de l’épaisseur du revêtement, donc à sa masse (voir aussi 7.3.2). Les produits couverts par le présent document peuvent être utilisés comme substrats pour des produits plats revêtus de matières organiques spécifiés dans l’EN 10169 pour des usages dans le bâtiment et la construction mécanique.

Kontinuirno vroče prevlečeni jekleni ploščati izdelki za hladno preoblikovanje - Tehnični dobavni pogoji

General Information

• Status: Not Published
• Publication Date: 29-Sep-2026
• ICS: 77.140.50 - Flat steel products and semi-products
• Technical Committee: ECISS/TC 109 - Coated and uncoated flat products to be used for cold forming
• Drafting Committee: ECISS/TC 109/WG 1 - Uncoated and coated flat products for cold forming and construction, except tin mill products
• Current Stage: 4060 - Closure of enquiry - Enquiry
• Start Date: 31-Jul-2025
• Due Date: 06-Aug-2025
• Completion Date: 31-Jul-2025
• Ref Project: oSIST prEN 10346:2025 - Continuously hot-dip coated steel flat products for cold forming - Technical delivery conditions

Relations

• Revises: EN 10346:2015 - Continuously hot-dip coated steel flat products for cold forming - Technical delivery conditions
• Effective Date: 28-Apr-2021

Overview

prEN 10346 - Continuously hot-dip coated steel flat products for cold forming - Technical delivery conditions (CEN draft, 2025) defines the technical delivery requirements for continuously hot‑dip coated steel strip and sheets intended for cold forming. The standard covers coated low‑carbon steels, steels for construction, high‑proof‑strength steels and multiphase steels coated with zinc (Z), zinc‑iron (ZF), zinc‑aluminium (ZA), zinc‑magnesium (ZM), aluminium‑silicon (AS) or aluminium (A) in thicknesses 0.20 mm ≤ t ≤ 6.5 mm (with optional agreement for t < 0.20 mm). It applies to strips of all widths and to sheets cut from them (≥ 600 mm width) and cut lengths (< 600 mm width). The products are commonly used where cold formability, defined yield strength and corrosion resistance are key.

Key topics and technical requirements

• Scope and classification: steel families (low‑carbon, construction, high‑proof‑strength, multiphase) and designation rules.
• Chemical and mechanical properties: specified composition limits and minimum mechanical performance tailored to cold forming and structural use.
• Coating types and coating mass: requirements for coating chemistry and mass for Z, ZF, ZA, ZM, AS and A coatings; methods for coating mass determination are referenced in normative annexes.
• Surface quality and finish: definitions for coating finish, surface protection (passivation, oiling, phosphating, sealing) and roughness/tolerances.
• Adhesion and suitability for further processing: tests and acceptance criteria for adhesion, stretchability, coating impact and formability for downstream processes.
• Inspection and testing: rules for sampling, test units, tensile tests and specific test methods (including annexes with reference methods).
• Delivery conditions: marking, packing, storage and transport provisions and options to agree additional properties at enquiry/order.

Practical applications and users

prEN 10346 is used by:

• Steel producers and hot‑dip coaters to manufacture and certify coated strip and sheet for cold forming.
• Specifiers, architects and structural engineers selecting coated substrates for building cladding, roofing, facades and cold‑formed structural elements.
• Manufacturers and fabricators of cold‑formed components (e.g., profiles, sections, panels) who require defined mechanical properties, coating durability and formability.
• Procurement and quality teams enforcing delivery conditions, inspection regimes and acceptance criteria.

The standard helps ensure consistent corrosion resistance, coating adhesion and mechanical performance for downstream organic coating (see EN 10169) and cold‑formed structural applications.

Related standards

• Supersedes EN 10346:2015 (draft prEN 10346:2025).
• Normative references added: EN 10373, EN 1090‑4, EN 1993‑1‑1, EN 1993‑1‑3.
• Cross‑reference: EN 10169 for organic coated flat products.

Keywords: prEN 10346, hot‑dip coated steel, cold forming, zinc coating, zinc‑aluminium, zinc‑magnesium, multiphase steels, coating mass, corrosion resistance, technical delivery conditions.

Standards Content (Sample)

SLOVENSKI STANDARD
01-julij-2025
Kontinuirno vroče prevlečeni jekleni ploščati izdelki za hladno preoblikovanje -
Tehnični dobavni pogoji
Continuously hot-dip coated steel flat products for cold forming - Technical delivery
conditions
Kaltgewalzte kontinuierlich schmelztauchveredelte Flacherzeugnisse aus Stahl -
Technische Lieferbedingungen
Produits plats en acier revêtus en continu par immersion à chaud pour formage à froid -
Conditions techniques de livraison
Ta slovenski standard je istoveten z: prEN 10346
ICS:
77.140.50 Ploščati jekleni izdelki in Flat steel products and semi-
polizdelki products
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

DRAFT
EUROPEAN STANDARD
NORME EUROPÉENNE
EUROPÄISCHE NORM
May 2025
ICS 77.140.50 Will supersede EN 10346:2015
English Version
Continuously hot-dip coated steel flat products for cold
forming - Technical delivery conditions
Produits plats en acier revêtus en continu par Kaltgewalzte kontinuierlich schmelztauchveredelte
immersion à chaud pour formage à froid - Conditions Flacherzeugnisse aus Stahl - Technische
techniques de livraison Lieferbedingungen
This draft European Standard is submitted to CEN members for enquiry. It has been drawn up by the Technical Committee
CEN/TC 459/SC 9.
If this draft becomes a European Standard, CEN members are bound to comply with the CEN/CENELEC Internal Regulations
which stipulate the conditions for giving this European Standard the status of a national standard without any alteration.

This draft European Standard was established by CEN in three official versions (English, French, German). A version in any other
language made by translation under the responsibility of a CEN member into its own language and notified to the CEN-CENELEC
Management Centre has the same status as the official versions.

CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia,
Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway,
Poland, Portugal, Republic of North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Türkiye and
United Kingdom.
Recipients of this draft are invited to submit, with their comments, notification of any relevant patent rights of which they are
aware and to provide supporting documentation.

Warning : This document is not a European Standard. It is distributed for review and comments. It is subject to change without
notice and shall not be referred to as a European Standard.

EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION

EUROPÄISCHES KOMITEE FÜR NORMUNG

CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels
© 2025 CEN All rights of exploitation in any form and by any means reserved Ref. No. prEN 10346:2025 E
worldwide for CEN national Members.

Contents Page
European foreword . 4
1 Scope . 5
2 Normative references . 5
3 Terms and definitions . 5
4 Classification and designation . 9
4.1 Classification . 9
4.1.1 General . 9
4.1.2 Low carbon steels for cold forming . 10
4.1.3 Steels for construction . 10
4.1.4 Steels with high proof strength for cold forming . 10
4.1.5 Multiphase steels for cold forming . 10
4.2 Designation . 10
4.2.1 Steel names . 10
4.2.2 Steel numbers . 10
5 Information to be supplied by the purchaser . 10
5.1 Mandatory information . 10
5.2 Options . 11
6 Manufacturing and processing. 12
6.1 Manufacturing . 12
6.2 Processing . 12
6.2.1 Ageing . 12
6.2.2 Coating appearance . 13
6.2.3 Surface protection . 13
7 Requirements . 13
7.1 Chemical composition . 13
7.2 Mechanical properties . 19
7.2.1 General . 19
7.2.2 Low carbon steels for cold forming . 20
7.2.3 Steels for construction . 23
7.2.4 Steels with high proof strength for cold forming . 24
7.2.5 Multiphase steels for cold forming . 25
7.3 Type of coatings and coating mass . 27
7.4 Coating finish . 32
7.4.1 General . 32
7.4.2 Zinc coated products (Z) . 32
7.4.3 Zinc-iron alloy coated products (ZF) . 32
7.4.4 Zinc-aluminium coated products (ZA) . 32
7.4.5 Zinc-magnesium coated products (ZM) . 32
7.4.6 Aluminium-silicon coated products (AS) . 32
7.4.7 Aluminium coated products (A) . 32
7.5 Surface quality . 32
7.5.1 General . 32
7.5.2 Types of surface qualities . 35
7.5.3 Roughness . 35
7.6 Surface treatment (surface protection) . 36
7.6.1 General . 36
7.6.2 Chemical passivation (C) . 36
7.6.3 Oiling (O) . 36
7.6.4 Chemical passivation and oiling (CO) . 36
7.6.5 Phosphating (P) . 37
7.6.6 Sealing (S) . 37
7.7 Coil breaks and bends (kinks) . 37
7.7.1 Freedom from coil breaks . 37
7.7.2 Bends (kinks) by winding on coiler drums . 37
7.8 Stretcher strains . 37
7.9 Coating mass . 37
7.10 Adhesion of coating . 38
7.11 Surface condition . 38
7.12 Tolerances on dimensions and shape . 38
7.13 Suitability for further processing . 38
8 Inspection . 38
8.1 Types of inspection and inspection documents. 38
8.2 Test units . 39
8.3 Tests to be carried out . 39
8.4 Sampling . 39
8.5 Test methods . 40
8.5.1 Tensile test . 40
8.5.2 Plastic strain ratio and hardening exponent . 41
8.5.3 Bake hardening index . 41
8.5.4 Surface inspection . 41
8.5.5 Coating mass . 41
8.6 Retests . 41
9 Marking . 41
10 Packing . 42
11 Storage and transportation . 42
Annex A (normative) Reference method for determination of the zinc, zinc-iron, zinc-
aluminium and zinc-magnesium coating mass . 43
Annex B (normative) Reference method for determination of the aluminium-silicon and
aluminium coating mass . 45
Annex C (normative) Reference method for determination of the mass of the Al-Fe-Si alloy
layer . 46
Annex D (informative) Tensile test results and coating impact . 47
Annex E (informative) Steel designations for multiphase steels for cold forming . 49
Bibliography . 51

European foreword
This document (prEN 10346:2025) has been prepared by Technical Committee CEN/TC 459/SC 9
“Coated and uncoated flat products to be used for cold forming”, the secretariat of which is held by
AFNOR.
This document is currently submitted to the CEN Enquiry.
This document will supersede EN 10346:2015.
— scope and normative references have been updated;
— addition of normative reference to:
o EN 10373, Determination of the physical and mechanical properties of steels using models;
o EN 1090-4, Execution of steel structures and aluminium structures - Part 4: Technical
requirements for cold-formed structural steel elements and cold-formed structures for roof, ceiling,
floor and wall applications
o EN 1993-1-1, Eurocode 3 - Design of steel structures - Part 1-1: General rules and rules for buildings
o EN 1993-1-3, Eurocode 3 - Design of steel structures - Part 1-3: General rules - Supplementary rules
for cold-formed members and sheeting
— definitions have been added in Clause 3;
— addition of hot-dip aluminium coating and deletion of hot-dip aluminium-zinc alloy coating;
— addition of three new steel families: dual-phase steels with improved formability (XH), complex-
phase steels with improved formability (CH) and multi-phase steels with improved formability (AH);
— addition of options referring to new steel grades S550GDR and S650GDR in Clause 5.2;
— addition of three new steel grades for construction: S500GD, S550GDR and S650GDR;
— addition of two new micro-alloyed steel grades: HX600LAD and HX700LAD;
— addition of minimum requirements regarding proportional elongation of steel grades for
construction and micro-alloyed steel grades with thickness ≥ 3,0 mm;
— addition of cold-rolled multiphase steels for cold forming: HCT780XG, HCT1180X, HCT1180XG,
HCT590XH, HCT780XH, HCT980XH, HCT1180XH, HCT1180C, HCT980CH, HCT1180CH, HCT1370CH,
HCT980AH and HCT1180AH;
— addition of hot-rolled multiphase steels for cold forming: HDT760C and HDT950C;
— addition of an informative Annex about tensile tests results and coating impact;
— addition of an informative Annex about steel designations for multiphase steels for cold forming.
1 Scope
This document specifies requirements for continuously hot-dip coated products made of low carbon
steels for cold forming, of steels for construction and of steels with high proof strength for cold forming
coated with zinc (Z), zinc-iron alloy (ZF), zinc-aluminium alloy (ZA), zinc-magnesium alloy (ZM),
aluminium-silicon alloy (AS) or aluminium (A) and for continuously hot-dip coated products made of
multiphase steels for cold forming coated with zinc (Z), zinc-iron alloy (ZF), zinc-aluminium alloy (ZA) or
zinc-magnesium alloy (ZM) in thicknesses of 0,20 mm ≤ t ≤ 6,5 mm.
By agreement at the time of enquiry and order, this document is applicable to continuously hot-dip coated
flat products of an expanded validity range defined for thicknesses t < 0,20 mm with agreed mechanical
properties and test specimens, adhesion of coating and surface condition requirements. This document
applies to strip of all widths and to sheets cut from it (≥600 mm width) and cut lengths (<600 mm width).
NOTE The products covered by this document are used where cold formability, high strength, a defined
minimum yield strength and/or corrosion resistance are the most important factors. Corrosion resistance of the
product is depending on coating type and coating thickness, hence to its mass (see also 7.3.2). The products covered
by this document can be used as substrates for organic coated flat products specified in EN 10169 for building and
general engineering applications.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements of this document. For dated references, only the edition cited applies. For
undated references, the latest edition of the referenced document (including any amendments) applies.
EN 10020, Definition and classification of grades of steel
EN 10021, General technical delivery conditions for steel products
EN 10027-1, Designation systems for steels — Part 1: Steel names
EN 10027-2, Designation systems for steels — Part 2: Numerical system
EN 10049, Measurement of roughness average Ra and peak count RPc on metallic flat products
EN 10079, Definition of steel products
EN 10143, Continuously hot-dip coated steel sheet and strip — Tolerances on dimensions and shape
EN 10204, Metallic products — Types of inspection documents
EN 10325, Steel — Determination of yield strength increase by the effect of heat treatment [Bake-
Hardening-Index]
EN ISO 6892-1, Metallic materials — Tensile testing — Part 1: Method of test at room temperature
(ISO 6892-1)
EN ISO 10113, Metallic materials — Sheet and strip — Determination of plastic strain ratio (ISO 10113)
EN ISO 10275, Metallic materials — Sheet and strip — Determination of tensile strain hardening exponent
(ISO 10275)
3 Terms and definitions
For the purposes of this document, the terms and definitions given in EN 10020, EN 10021, EN 10079,
EN 10204 and the following apply.
ISO and IEC maintain terminology databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https://www.iso.org/obp/
— IEC Electropedia: available at https://www.electropedia.org/
NOTE General definitions and guidelines for the protection of iron and steel can be found in EN ISO 14713-1.
3.1
nominal (specified) thickness
ordered thickness of the metallic coated product
Note 1 to entry: Nominal thickness includes both steel core and coating (t )
nom
3.2
steel core thickness
nominal (specified) thickness minus the metallic coating layers
Note 1 to entry: The steel core thickness is in accordance with the definition in EN 1993-1-3 (t ). It is the design
cor
thickness for calculations in accordance with EN 1993-1-3.
3.3
hot-dip zinc coating
Z
application of a zinc coating by immersing the prepared strip in a molten bath of zinc
Note 1 to entry: The zinc content is at least 98,5 mass %.
Note 2 to entry: See also 7.4.2.
3.4
hot-dip zinc-iron alloy coating
ZF
application of a zinc-iron coating by immersing the prepared strip in a molten bath of zinc and a
subsequent annealing
Note 1 to entry: The zinc content of the bath is at least 99 mass %.
Note 2 to entry: The annealing produces an iron-zinc coating with an iron content of normally 8 mass % to 12 mass
%.
Note 3 to entry: See also 7.4.3.
3.5
hot-dip zinc-aluminium coating
ZA
application of a zinc-aluminium coating by immersing the prepared strip in a molten bath of zinc-
aluminium
Note 1 to entry: The composition of the bath is approximately 5 mass % aluminium, small amounts of mischmetal
and the balance zinc.
Note 2 to entry: See also 7.4.4.
3.6
hot dip zinc-magnesium coating
ZM
application of a zinc-magnesium coating by immersing the prepared strip in a molten bath of zinc-
aluminium-magnesium
Note 1 to entry: The composition of the bath is sum of aluminium and magnesium from 1,5 mass % to 8 mass %,
containing minimum of 0,2 mass % magnesium and the balance zinc.
Note 2 to entry: For information on chemical composition and density, the manufacturer can be asked for advice.
Note 3 to entry: Due to differences in coating bath chemistry, the properties provided by each coating can differ
(e.g surface aspect, processability, corrosion resistance) and the manufacturer can be asked for advice.
Note 4 to entry: See also 7.4.5.
3.7
hot-dip aluminium-silicon alloy coating
AS
application of an aluminium-silicon coating by immersing the prepared strip in a molten bath of
aluminium-silicon
Note 1 to entry: The composition of the bath is 8 to 11 mass % silicon, up to 5 mass % iron, up to 1 mass %
additional elements and the balance aluminium.
Note 2 to entry: See also 7.4.6.
3.8
hot-dip aluminium coating
A
application of an aluminium coating by immersing the prepared strip in a molten bath of pure aluminium
Note 1 to entry: The iron content in the bath is less than 5 mass %.
Note 2 to entry: see also 7.4.7.
3.9
coating mass
total mass of coating given for both surfaces
Note 1 to entry: In combination with the symbol for the coating type (Z, ZF, ZA, ZM, AS,A), the nominal coating mass
is used as coating designation.
Note 2 to entry: The coating mass is expressed in grams per square metre.
Note 3 to entry: See 7.9.
3.10
bake-hardening steel
B
steel exhibiting an increase in proof strength following heating in the region of 170°C for 20 min
Note 1 to entry: These steels have a good suitability for cold forming and present a high resistance to plastic
straining (which is increased on finished parts during heat treatment) and a good dent resistance.
3.11
complex-phase steel
C
steel with a multiphase microstructure containing mainly bainite, ferrite, whereas martensite, tempered
martensite, retained austenite and pearlite may be present as additional phases
Note 1 to entry: The fine grained microstructure can be generated by retarded recrystallization or precipitation of
micro-alloying elements.
3.12
complex-phase steel with improved formability
CH
steel consisting mainly of martensite, bainite and retained austenite
Note 1 to entry: Depending on strength class, small amounts of ferrite can also be present.
Note 2 to entry: At a given high tensile strength, complex phase steels with improved formability show a high yield
ratio (Re/Rm).
3.13
dual-phase steel
X
steel consisting of mainly ferrite and martensite and possible bainite as a complementary phase
Note 1 to entry: According to their high tensile strength levels, dual phase steels show a low yield strength ratio
and a high work hardening rate.
3.14
dual-phase steel with improved formability
XH
steel consisting mainly of ferrite and martensite and small amounts of bainite and retained austenite
Note 1 to entry: According to their high tensile strength levels, dual phase steels with improved formability show
higher uniform elongation.
3.15
ferritic-bainitic steel
F
steel with a matrix of ferrite or strengthened ferrite containing bainite or strengthened bainite
Note 1 to entry: The strengthening of the matrix is caused by a high density of dislocations, by grain refinement
and precipitation of micro-alloying elements.

Symbol used in the steel name (see Tables 3, 4 and 5).
3.16
high strength interstitial free steel
Y
steel whose composition is controlled to achieve improved plastic strain ratio r and strain hardening
exponent n values
Note 1 to entry: These steels have both, a high mechanical strength and an excellent suitability for cold forming,
due to their solid solution hardening and interstitial free microstructure.
3.17
low alloy steel
micro-alloyed steel
LA
steel containing one or more of alloying elements Nb, Ti and V to achieve required proof strength levels
Note 1 to entry: Combined precipitation and grain refinement hardening modes allow reaching a high mechanical
resistance while reducing the content of alloying elements.
Note 2 to entry: Alternatively, carbon-manganese alloying concepts in combination with grain refinement can be
used.
3.18
low carbon steel
steel with low carbon content characterized by low yield strength and high ductility
3.19
multi-phase steels with high global formability
AH
steel containing a combination of tempered martensite, bainite and retained austenite
Note 1 to entry: Ferrite and martensite can be present.
3.20
steel for construction
steel with minimum strength levels and no special demand for suitability for cold forming
3.21
transformation induced plasticity steel
T
steel with a ferritic matrix containing retained austenite capable of transformation into martensite during
the forming process (TRIP effect)
Note 1 to entry: Because of high work-hardening rate the steel reaches high uniform elongation values and high
tensile strength levels.
4 Classification and designation
4.1 Classification
4.1.1 General
The steels covered by this document are either alloy quality steels or non-alloy quality steels in
accordance with EN 10020. All steels in Tables 1, 3, 4, 5 and steel grade S650GDR in Table 2 are alloy
quality steels. All steels in Table 2 with the exception of S650GDR are non-alloy quality steels.
4.1.2 Low carbon steels for cold forming
The steel grades are classified in accordance with their increasing suitability for cold forming as follows
(see Table 7):
— DX51D: bending and profiling quality;
— DX52D: drawing quality;
— DX53D: deep drawing quality;
— DX54D: special deep drawing quality;
— DX55D: special deep drawing quality (only +AS);
— DX56D: extra deep drawing quality;
— DX57D: super deep drawing quality;
— DX58D: extra super deep drawing quality.
Only steel grades DX51D, DX52D and DX53D can be ordered as hot rolled products.
4.1.3 Steels for construction
The steel grades are classified in accordance with their increasing minimum proof strength Rp (see
0,2
Table 8).
4.1.4 Steels with high proof strength for cold forming
The steel grades are classified in accordance with their increasing minimum proof strength Rp (see
0,2
Table 9).
Only low alloy/micro-alloyed steel grades can be ordered as hot rolled products.
4.1.5 Multiphase steels for cold forming
The steel grades are classified in accordance with their increasing minimum tensile strength Rm (see
Tables 10 and 11). See Annex E for the steel names and steel numbers of advanced high strength steels
(AHSS).
4.2 Designation
4.2.1 Steel names
The steel names shall be in accordance with EN 10027-1.
4.2.2 Steel numbers
The steel numbers shall be in accordance with EN 10027-2.
5 Information to be supplied by the purchaser
5.1 Mandatory information
The following information shall be supplied by the purchaser at the time of enquiry and order:
a) quantity to be delivered;
b) type of product (strip, sheet, cut length);
c) number of the dimensional standard in accordance with EN 10143;
d) nominal dimensions and the tolerances on dimensions and shape and, if applicable, letters denoting
relevant special tolerances;
e) term “steel”;
f) number of this document, i.e. EN 10346;
g) steel name or steel number and symbol for the type of hot-dip coating as given in Tables 1 to 5;
h) number designating the nominal mass of coating (e.g. 275 = 275 g/m including both surfaces, see
Table 12);
i) letter denoting the coating finish (N or M, see 7.4.2 and Table 13);
j) letter denoting the surface quality (A, B or C, see 7.5 and Tables 13 to 15);
k) letter denoting the surface treatment (C, O, CO, P, PO or S, see 7.6);
l) if relevant (see 8.5.1), selection of the test piece (proportional (A ) or non-proportional (A )
prop 80
specimen) for determination of the mechanical properties.
EXAMPLE 1 sheet, delivered with dimensional tolerances in accordance with EN 10143 with nominal
thickness of 0,80 mm, ordered with special thickness tolerances (S), nominal width 1 200 mm, ordered with special
width tolerances (S), nominal length 2 500 mm, ordered with special flatness tolerances (FS), made of steel
DX53D+Z (1.0951+Z) in accordance with EN 10346, coating mass 100 g/m (100), minimized spangle (M), surface
quality (B), surface treatment oiled (O):
1 sheet EN 10143 — 0,80Sx1200Sx2500FS — steel EN 10346 — DX53D+Z100–M–B–O
or:
1 sheet EN 10143 — 0,80Sx1200Sx2500FS — steel EN 10346 — 1.0951+Z100 –M–B–O.
5.2 Options
A number of options are specified in this document and listed below. lf the purchaser does not indicate a
wish to implement any of these options, the products shall be supplied in accordance with the basis
specification of this document (see 5.1).
1) specification of product thicknesses deviating from those generally covered in the scope (i.e.
t < 0,20 mm) (see Scope);
2) verification of the product analysis (see 7.1);
3) date of supply for products free from stretcher strains when cold forming (see 7.2.1.3);
4) products supplied suitable for the manufacture of a specific part (see 7.2.2.2 and 7.2.4.2);
5) supply of steel grade S550GDR with specified minimum ratio Rm/Re ≥ 1,10 and A ≥ 15 % for
prop
dimensioning in accordance with EN 1993-1-1 (see 7.2.3 – Table 8), where Re is either Rp or Re in
02 H
dependence of yield point phenomenon (footnote b, Table 8).
In case of organic coated steel, this option 5 is upon agreement of the manufacturer.
6) Supply of steel grade S550GDR or S650GDR with specified minimum ratio Rm/Re ≥ 1,05 for
dimensioning in accordance with EN 1993-1-1 (see 7.2.3 – Table 8), where Re is either Rp or Re in
02 H
dependence of yield point phenomenon (footnote b, Table 8).
In case of organic coated steel, this option 6 is upon agreement of the manufacturer.
7) coating masses different from those of Table 12 and/or special requirements for different coating
masses on each surface (see 7.3.2);
8) special coatings and/or surface qualities (see Tables 13 and 15, footnote a);
9) hot-dip zinc coated products with pronounced spangle (see 7.4.2.1);
10) special requirements for a maximum Al-Fe-Si alloy layer mass occurring during hot-dip aluminium-
silicon coating (see 7.4.7);
11) hot-dip coated products with surface quality A without skin passing (see 7.5.2.1);
12) requirement for special applications on bright appearance for aluminium-silicon coated products
(type B surface, see NOTE to 7.5.2.2);
13) range and verification of surface roughness (see 7.5.3);
14) selection of the protective oil (see 7.6.1);
15) type of S coating (see 7.6.6);
16) products free from coil breaks (see 7.7.1);
17) type of inspection and, if applicable, inspection document to be delivered (see 8.1);
18) notification of which surface has been inspected (see 8.5.4.2);
19) marking desired by branding of the products (see 9.2);
20) requirement for packing (see Clause 10);
21) according to EN 1090-4
i) determination of the ratio bend radius to thickness, if relevant;
ii) display of the result of the adhesion test in the inspection document (see 7.10).
6 Manufacturing and processing
6.1 Manufacturing
Unless there are restrictions by the selected steel grade, the processes used in steelmaking and the
manufacture of the products shall be left to the discretion of the manufacturer.
6.2 Processing
6.2.1 Ageing
Due to ageing, a reduction in formability can take place for all the products supplied according to this
document. Coil breaks or fluting can occur additionally during processing. The risk of coil breaks
increases, especially for thicknesses > 0,9 mm, with the duration of storage.
Therefore the user should process the products after their receipt as quick as possible (see 7.2.1.3).
6.2.2 Coating appearance
The coating surface can vary and change to a dark appearance by oxidation.
Due to ageing of the coating a certain cracking of the surface can appear during processing which can
consequently reduce abrasion resistance.
The user should take these characteristics into account.
6.2.3 Surface protection
Regarding surface protection during transport and storage the following should be taken into
consideration:
— Only a temporary corrosion resistance during transportation or storage is provided by any surface
protection applied. Colour changes can occur.
— In particular, protection by oiling is dependent on storage time. The primarily uniform oil film
becomes more and more unequal, and bare spots can develop. Different oils can show different
behaviour.
7 Requirements
7.1 Chemical composition
The chemical composition according to the cast analysis shall be as specified in Tables 1 to 5.
If a product analysis is agreed at the time of enquiry and order, the permitted deviations from the cast
analysis given in Tables 1 to 5 shall meet the requirements in Table 6.
Table 1 — Chemical composition (cast analysis) of low carbon steels for cold forming
Chemical composition
Designation % by mass
max.
Steel grade
Symbols for the types of
a
C Si Mn P S Ti
Steel Steel
available coatings
name number
DX51D 1.0917 +Z,+ZF,+ZA,+ZM, +AS 0,18  1,20 0,12
DX52D 1.0918 +Z,+ZF,+ZA,+ZM, +AS
DX53D 1.0951 +Z,+ZF,+ZA,+ZM, +AS
DX54D 1.0952 +Z,+ZF,+ZA,+ZM, +AS
DX55D 1.0962 +AS 0,12 0,50 0,60 0,10 0,045 0,30
DX56D 1.0963 +Z,+ZF,+ZA,+ZM, +AS
DX57D 1.0853 +Z,+ZF,+ZA,+ZM,+AS
DX58D 1.9946 +Z
a
By agreement at the time of enquiry and order, the content of Ti for the steel grades mentioned in
this Table may be lowered to < 0,05 % which means that the steel grade is non alloyed.
Table 2 — Chemical composition (cast analysis) of steels for construction
Chemical composition
Designation % by mass
max.
Steel grade
Symbols for the types of
C Si Mn P S
Steel
available coatings
Steel name
number
S220GD 1.0241 +Z,+ZF,+ZA,+ZM, +A
S250GD 1.0242 +Z,+ZF,+ZA,+ZM, +AS, +A
S280GD 1.0244 +Z,+ZF,+ZA,+ZM, +AS, +A
S320GD 1.0250 +Z,+ZF,+ZA,+ZM, +AS, +A
S350GD 1.0529 +Z,+ZF,+ZA,+ZM, +AS, +A
S390GD 1.0238 +Z,+ZF,+ZA,+ZM 0,20 0,60 1,70 0,10 0,045
S420GD 1.0239 +Z,+ZF,+ZA,+ZM
S450GD 1.0233 +Z,+ZF,+ZA,+ZM
S500GD 1.9527 +Z,+ZF,+ZA,+ZM
S550GD 1.0531 +Z,+ZF,+ZA,+ZM
Steels for construction with specified minimum ductility (R)
a
S550GDR 1.9541 +Z,+ZA,+ZM 0,20 0,60 1,70 0,10 0,045
a
S650GDR 1.9542 +Z, +ZA,+ZM 0,2 0,6 2,00 0,10 0,045
By agreement at the time of enquiry and order, if other chemical elements are added, they shall be
mentioned on the inspection document which may need a change of classification.
a
R means steel grade with specified minimum ductility, because these steels show a high total elongation in
relation to high strengths.
Table 3 — Chemical composition (cast analysis) of steels
with high proof strength for cold forming
Chemical composition
Steel grade
% by mass
+Z,+ZF,+ZA, +ZM, +AS C Si Mn P S Al Nb Ti
total
Steel name Steel number max. max. max. max. max.  max. max.
HX160YD 1.0910 0,01 0,30 0,60 0,060 0,025 ≥ 0,010 0,09 0,12
HX180YD 1.0921 0,01 0,30 0,70 0,060 0,025 ≥ 0,010 0,09 0,12
HX180BD 1.0914 0,06 0,50 0,70 0,060 0,025 ≥ 0,015 0,09 0,12
HX220YD 1.0923 0,01 0,30 0,90 0,080 0,025 ≥ 0,010 0,09 0,12
HX220BD 1.0919 0,08 0,50 0,70 0,085 0,025 ≥ 0,015 0,09 0,12
HX260YD 1.0926 0,01 0,30 1,60 0,10 0,025 ≥ 0,010 0,09 0,12
HX260BD 1.0924 0,10 0,50 1,00 0,10 0,030 ≥ 0,010 0,09 0,12
HX260LAD 1.0929 0,11 0,50 1,00 0,030 0,025 ≥ 0,015 0,09 0,15
HX300YD 1.0927 0,015 0,30 1,60 0,10 0,025 ≥ 0,010 0,09 0,12
HX300BD 1.0930 0,11 0,50 0,80 0,12 0,025 ≥ 0,010 0,09 0,12
HX300LAD 1.0932 0,12 0,50 1,40 0,030 0,025 ≥ 0,015 0,09 0,15
HX340BD 1.0945 0,11 0,50 0,80 0,12 0,025 ≥ 0,010 0,09 0,12
HX340LAD 1.0933 0,12 0,50 1,4 0,030 0,025 ≥ 0,015 0,10 0,15
HX380LAD 1.0934 0,12 0,50 1,5 0,030 0,025 ≥ 0,015 0,10 0,15
HX420LAD 1.0935 0,12 0,50 1,6 0,030 0,025 ≥ 0,015 0,10 0,15
HX460LAD 1.0990 0,15 0,50 1,7 0,030 0,025 ≥ 0,015 0,10 0,15
HX500LAD 1.0991 0,15 0,50 1,7 0,030 0,025 ≥ 0,015 0,10 0,15
HX600LAD 1.9950 0,15 0,50 2,0 0,030 0,025 ≥ 0,015 0,10 0,15
HX700LAD 1.9951 0,15 0,50 2,0 0,030 0,025 ≥ 0,015 0,10 0,17
Table 4 — Chemical composition (cast analysis) of multiphase steels
for cold forming (cold rolled products)
Chemical composition
Steel grade % by mass
+Z,+ZF,+ZM
Cr + Nb +
C Si Mn P S Al B
total
Mo Ti
Steel name Steel number max. max. max. max. max.  max. max. max.
Dual-phase steels (X)
0,015 to
HCT450X 1.0937 0,14 0,75 2,00 0,080 0,015
1,00 0,15 0,005
1,0
0,015 to
HCT490X 1.0995 0,14 0,50 1,80 0,050 0,010 1,00 0,15 0,005
1,0
0,015 to
HCT590X 1.0996 0,15 0,80 2,50 0,050 0,010 1,40 0,15 0,005
1,5
0,015 to
HCT780X 1.0943 0,18 0,80 2,50 0,050 0,010 1,40 0,15 0,005
2,0
0,015 to
a
HCT780XG 1.9926 0,18 0,80 2,50 0,05 0,01 1,4 0,15 0,005
1,0
0,015 to
HCT980X 1.0944 0,20 1,00 2,90 0,050 0,010 1,40 0,15 0,005
2,0
0,015 to
a
HCT980XG 1.0997 0,23 1,00 2,90 0,050 0,010 1,40 0,15 0,005
2,0
0,015 to
HCT1180X 1.9929 0,25 1,00 2,90 0,050 0,010 1,40 0,15 0,005
1,0
0,015 to
a
HCT1180XG 1.9930 0,20 1,00 2,90 0,050 0,010 1,40 0,15 0,005
1,0
Dual-phase steels with improved formability (XH)
0,015 to
HCT590XH 1.9931 0,15 0,80 2,50 0,050 0,010 1,40 0,15 0,005
1,0
0,015 to
HCT780XH 1.9932 0,18 0,80 2,50 0,050 0,010 1,40 0,15 0,005
1,0
0,015 to
HCT980XH 1.9933 0,23 1,20 2,90 0,050 0,010 1,40 0,15 0,005
1,0
0,015 to
HCT1180XH 1.9934 0,25 1,50 2,90 0,050 0,010 1,40 0,15 0,005
1,0
Transformation induced plasticity steels (T)
0,015 to
HCT690T 1.0947 0,24 2,00 2,20 0,050 0,010 0,60 0,20 0,005
2,0
0,015 to
HCT780T 1.0948 0,25 2,20 2,50 0,050 0,010 0,60 0,20 0,005
2,0
Chemical composition
Steel grade % by mass
+Z,+ZF,+ZM
Cr + Nb +
C Si Mn P S Al B
total
Mo Ti
Steel name Steel number max. max. max. max. max.  max. max. max.
Complex-phase steels (C)
0,015 to
HCT600C 1.0953 0,18 0,80 2,20 0,080 0,015 1,00 0,15 0,005
2,0
0,015 to
HCT780C 1.0954 0,18 1,00 2,50 0,050 0,010 1,00 0,15 0,005
1,0
0,015 to
HCT980C 1.0955 0,23 1,00 2,70 0,050 0,010 1,00 0,15 0,005
1,0
0,015 to
HCT1180C 1.9928 0,23 1,00 2,90 0,050 0,010 1,00 0,15 0,005
1,0
Complex-phase steels with improved formability (CH)
0,015 to
HCT980CH 1.9935 0,20 1,20 3,00 0,050 0,015 1,00 0,15 0,005
1,0
0,015 to
HCT1180CH 1.9936 0,23 1,20 3,00 0,050 0,010 1,00 0,15 0,005
1,0
0,015 to
HCT1370CH 1.9937 0,26 1,20 3,00 0,050 0,010 1,00 0,15 0,005
1,0
Multi-phase steels with high global formability (AH)
0,015 to
HCT980AH 1.9938 0,26 2,20 2,50 0,050 0,010 1,40 0,15 0,005
2,0
0,015 to
HCT1180AH 1.9939 0,26 2,20 3,00 0,050 0,010 1,40 0,15 0,005
2,0
a
XG means dual-phase steel with increased yield strength.
Table 5 — Chemical composition (cast analysis) of multiphase steels
for cold forming (hot rolled products)
Chemical composition
Steel grade % by mass
+Z,+ZF, +ZM
Cr + Nb +
C Si Mn P S Al B
total
Mo Ti
Steel
Steel name max. max max. max. max.  max. max. max.
number
Ferritic-bainitic steels (F)
0,015
HDT450F 1.0961 0,18 0,50 2,00 0,050 0,010 1,00 0,15 0,005
to 2,0
0,015
HDT580F 1.0994 0,18 0,50 2,00 0,050 0,010 1,00 0,15 0,01
to 2,0
Dual-phase steel (X)
0,015
HDT580X 1.0936 0,14 1,0 2,20 0,085 0,015 1,40 0,15 0,005
to 1,0
Complex-phase steels (C)
0,015
HDT760C 1.0998 0,18 1,00 2,20 0,050 0,010
1,00 0,25 0,005
to 1,2
0,015
HDT950C 1.0958 0,23 1,00 2,70 0,080 0,015 1,20 0,25 0,005
to 1,20
Table 6 — Permissible deviations of th
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