EN 2451:2025
(Main)Aerospace series - Steel 31NiMoCr10-5-3 - 1 230 MPa ≤ Rm ≤ 1 420 MPa - Forgings - De ≤ 40 mm
Aerospace series - Steel 31NiMoCr10-5-3 - 1 230 MPa ≤ Rm ≤ 1 420 MPa - Forgings - De ≤ 40 mm
This document specifies the requirements relating to:
Steel 31NiMoCr10-5-3
1 230 MPa ≤ Rm ≤ 1 420 MPa
Bars
De ≤ 40 mm
for aerospace applications.
ASD-STAN designation: FE-PL73.
Luft- und Raumfahrt - Stahl 31NiMoCr10 5 3 - 1 230 MPa ≤ Rm ≤ 1 420 MPa - Schmiedestücke - De ≤ 40 mm
Dieses Dokument legt die Anforderungen an:
Stahl 31NiMoCr10 5 3
1 230 MPa ≤ Rm ≤ 1 420 MPa
Schmiedestücke
De ≤ 40 mm
für Anwendungen in der Luft- und Raumfahrt fest.
ASD-STAN-Bezeichnung: FE-PL73.
Série aérospatiale - Acier 31NiMoCr10-5-3 - 1 230 MPa ≤ Rm ≤ 1 420 MPa - Pièces forgées ou matricées - De ≤ 40 mm
Le présent document spécifie les exigences relatives à :
Acier 31NiMoCr10-5-3
1 230 MPa ≤ Rm ≤ 1 420 MPa
Barres
De ≤ 40 mm
pour les applications aérospatiales.
Désignation ASD-STAN : FE-PL73.
Aeronavtika - Jeklo 31NiMoCr10-5-3 - 1230 MPa ≤ Rm ≤ 1420 MPa - Izkovki - De ≤ 40 mm
General Information
- Status
- Published
- Publication Date
- 18-Nov-2025
- Technical Committee
- ASD-STAN - Aerospace
- Drafting Committee
- ASD-STAN/D 4/S 3 - Steels & Heat Resisting Alloys
- Current Stage
- 6060 - Definitive text made available (DAV) - Publishing
- Start Date
- 19-Nov-2025
- Completion Date
- 19-Nov-2025
Relations
- Replaces
EN 2451:2019 - Aerospace series - Steel 31Ni10 - 1 230 MPa ≤ Rm ≤ 1 420 MPa - Forgings - De ≤ 40 mm - Effective Date
- 30-Aug-2023
Overview
EN 2451:2025 - Aerospace series - Steel 31NiMoCr10‑5‑3 - 1 230 MPa ≤ Rm ≤ 1 420 MPa - Forgings (De ≤ 40 mm) is a CEN/ASD‑STAN material standard (ASD‑STAN designation: FE‑PL73) that defines chemical, mechanical and delivery requirements for forgings/bars of steel 31NiMoCr10‑5‑3 intended for aerospace use. Approved October 2025 and superseding EN 2451:2019, it applies to forged products with external diameter (De) up to 40 mm and establishes acceptance criteria for heat treatment, strength, hardness and other properties.
Key topics and technical requirements
- Material designation: Steel 31NiMoCr10‑5‑3 (typical use: low‑alloy, general purpose aerospace steel).
- Chemical composition (wt % ranges): C 0.27–0.35; Si 0.15–0.35; Mn 0.45–0.70; P ≤ 0.025; S ≤ 0.020; Cr 0.50–0.80; Mo 0.45–0.65; Ni 2.30–2.80.
- Melting method: Air melted.
- Form and size: Forgings / bars with De ≤ 40 mm.
- Delivery conditions & heat treatment: Softened, or hardened and tempered with austenitizing at 840–860 °C (oil quench) and tempering at ≥ 520 °C.
- Mechanical properties (hardened & tempered):
- Tensile strength Rm: 1 230 ≤ Rm ≤ 1 420 MPa
- Proof stress Rp0.2: ≥ 1 080 MPa
- Elongation A: ≥ 9 %
- Reduction of area Z: ≥ 40 %
- Impact strength: ≥ 20 (as specified)
- Hardness:
- Softened: HB ≤ 248
- Hardened & tempered: HB 363–415 (HV values also given; special note for De ≤ 5 mm)
- Hardenability (Jominy): Minimum HRC specified at distances 6, 10, 16, 25, 40 mm (49, 48, 48, 47, 47 HRC respectively).
- Referenced specs: EN 4700‑005 for forging stock technical specification.
Applications and who uses this standard
EN 2451:2025 is used by:
- Aerospace materials engineers and designers specifying high‑strength forged components.
- Forging and heat‑treatment manufacturers producing bars/forgings to aerospace quality.
- Purchasing and quality assurance teams for procurement, inspection and acceptance criteria.
- Certification bodies and testing labs performing mechanical, hardness and hardenability testing.
Typical application domains include aerospace structural and mechanical components where a combination of very high tensile strength, toughness and controlled hardenability is required.
Related standards
- EN 4700‑005 - Aerospace series - Wrought products - Technical specification - Part 005: Forging stocks
- EN 4258 - Organization of metallic material standards for aerospace
- EN 4500‑005 - Rules for drafting/presentation of steel material standards
Keywords: EN 2451:2025, Steel 31NiMoCr10‑5‑3, aerospace forgings, Rm 1230‑1420 MPa, hardened and tempered, forgings De ≤ 40 mm, FE‑PL73, CEN, ASD‑STAN.
Frequently Asked Questions
EN 2451:2025 is a standard published by the European Committee for Standardization (CEN). Its full title is "Aerospace series - Steel 31NiMoCr10-5-3 - 1 230 MPa ≤ Rm ≤ 1 420 MPa - Forgings - De ≤ 40 mm". This standard covers: This document specifies the requirements relating to: Steel 31NiMoCr10-5-3 1 230 MPa ≤ Rm ≤ 1 420 MPa Bars De ≤ 40 mm for aerospace applications. ASD-STAN designation: FE-PL73.
This document specifies the requirements relating to: Steel 31NiMoCr10-5-3 1 230 MPa ≤ Rm ≤ 1 420 MPa Bars De ≤ 40 mm for aerospace applications. ASD-STAN designation: FE-PL73.
EN 2451:2025 is classified under the following ICS (International Classification for Standards) categories: 49.025.10 - Steels. The ICS classification helps identify the subject area and facilitates finding related standards.
EN 2451:2025 has the following relationships with other standards: It is inter standard links to EN 2451:2019. Understanding these relationships helps ensure you are using the most current and applicable version of the standard.
EN 2451:2025 is available in PDF format for immediate download after purchase. The document can be added to your cart and obtained through the secure checkout process. Digital delivery ensures instant access to the complete standard document.
Standards Content (Sample)
SLOVENSKI STANDARD
01-januar-2026
Aeronavtika - Jeklo 31NiMoCr10-5-3 - 1230 MPa ≤ Rm ≤ 1420 MPa - Izkovki - De ≤
40 mm
Aerospace series - Steel 31NiMoCr10-5-3 - 1 230 MPa ≤ Rm ≤ 1 420 MPa - Forgings -
De ≤ 40 mm
Luft- und Raumfahrt - Stahl 31NiMoCr10-5-3 - 1 230 MPa ≤ Rm ≤ 1 420 MPa - Gesenk-
und Freiformschmiedestücke - De ≤ 40 mm
Série aérospatiale - Acier 31NiMoCr10-5-3 - 1 230 MPa ≤ Rm ≤ 1 420 MPa - Pièces
forgées ou matricées - De ≤ 40 mm
Ta slovenski standard je istoveten z: EN 2451:2025
ICS:
49.025.10 Jekla Steels
77.140.85 Železni in jekleni kovani Iron and steel forgings
izdelki
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
EN 2451
EUROPEAN STANDARD
NORME EUROPÉENNE
November 2025
EUROPÄISCHE NORM
ICS 49.025.10 Supersedes EN 2451:2019
English Version
Aerospace series - Steel 31NiMoCr10-5-3 - 1 230 MPa
Rm 1 420 MPa - Forgings - De 40 mm
Série aérospatiale - Acier 31NiMoCr10-5-3 - 1 230 MPa Luft- und Raumfahrt - Stahl 31NiMoCr10-5-3 - 1 230
Rm 1 420 MPa - Pièces forgées ou matricées - De MPa Rm 1 420 MPa - Gesenk- und
40 mm Freiformschmiedestücke - De 40 mm
This European Standard was approved by CEN on 5 October 2025.
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. Up-to-date lists and bibliographical references
concerning such national standards may be obtained on application to the CEN-CENELEC Management Centre or to any CEN
member.
This European Standard exists 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.
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. EN 2451:2025 E
worldwide for CEN national Members.
Contents Page
European foreword . 3
Introduction . 4
1 Scope . 5
2 Normative references . 5
3 Terms and definitions . 5
4 Requirements . 5
Bibliography . 9
European foreword
This document (EN 2451:2025) has been prepared by ASD-STAN.
After enquiries and votes carried out in accordance with the rules of this Association, this document has
received the approval of the National Associations and the Official Services of the member countries of
ASD-STAN, prior to its presentation to CEN.
This document shall be given the status of a national standard, either by publication of an identical text
or by endorsement, at the latest by May 2026, and conflicting national standards shall be withdrawn at
the latest by May 2026.
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CEN shall not be held responsible for identifying any or all such patent rights.
This document supersedes EN 2451:2019.
— correction of the French title
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