prEN 3523

• Status: Not Published
• Publication Date: 09-Aug-2027
• ICS: 49.025.10 - Steels
• Technical Committee: ASD-STAN - Aerospace
• Drafting Committee: ASD-STAN/D 4/S 3 - Steels & Heat Resisting Alloys
• Current Stage: 4060 - Closure of enquiry - Enquiry
• Start Date: 30-Apr-2026
• Completion Date: 30-Apr-2026
• Ref Project: oSIST prEN 3523:2026 - Aerospace series - Steel 15CrMoV6 (1.7334) - Air melted - Hardened and tempered - Bars for machining - De ≤ 100 mm - 1 080 MPa ≤ Rm ≤ 1 280 MPas

• Revises: EN 3523:2024 - Aerospace series - Steel 15CrMoV6 (1.7334) - Air melted - Hardened and tempered - Bars for machining - De ≤ 100 mm - 1 080 MPa ≤ Rm ≤ 1 280 MPa
• Effective Date: 14-Jan-2026

Overview

prEN 3523 is a draft European Standard developed by CEN for the aerospace sector, specifying requirements for steel 15CrMoV6 (1.7334). This standard covers air melted, hardened, and tempered bars intended for machining, with diameters up to 100 mm. The material is characterized by its high tensile strength range of 1,080 MPa to 1,280 MPa, making it suitable for aerospace applications demanding reliable performance under stress.

This document, set to supersede EN 3523:2024, aligns with ongoing advancements in engineering materials and supports consistent quality and safety in aerospace manufacturing. It serves both producers and users of steel bars in aviation and aerospace industries.

Key Topics

• Material specification: Defines the chemical composition and mechanical properties of steel 15CrMoV6 (1.7334).
• Production method: Requires air melting and specific heat treatment processes (hardening and tempering).
• Bar dimensions: Applies to bars with diameters up to 100 mm.
• Mechanical properties: Ensures bars meet stringent tensile strength and hardness values suitable for critical aerospace uses.
• Delivery conditions: Covers requirements for bars in either softened or hardened and tempered conditions.
• Testing and inspection: Details methods for verifying material quality, including:
  • Micrographic inclusion content (per EN 2951)
  • Hardenability (Jominy test per EN ISO 642)
  • Mechanical testing for proof and tensile strength, elongation, hardness, and impact toughness
  • Inspection for internal and external imperfections (visual and ultrasonic)
• Marking and traceability: Ensures all bars are properly marked according to EN 4700-002 for full traceability and compliance.

Applications

The primary focus of prEN 3523 is to provide standardized requirements for steel bars used in aerospace engineering and aircraft manufacturing. This ensures:

• Consistency in performance: By standardizing material properties and testing methods, manufacturers can rely on predictable performance in structural and mechanical parts.
• Enhanced safety: Meeting strict strength and toughness criteria minimizes risks associated with material failure in flight-critical applications.
• Efficient sourcing: Aerospace manufacturers and suppliers benefit from clear, harmonized guidelines, facilitating procurement and quality control.
• Machining suitability: The specified 15CrMoV6 steel composition and properties support high-precision machining, making it ideal for producing aircraft components and assemblies.

Related Standards

prEN 3523 references and is aligned with several key standards to ensure comprehensive coverage of material and production requirements:

• EN 2043: Aerospace series - General requirements for qualification of semi-finished metallic products
• EN 2951: Methods for micrographic determination of non-metallic inclusions in aerospace metallic materials
• EN 4700-002: Technical specification for wrought steel and heat resisting alloy bars and sections
• EN ISO 642: Steel hardenability testing methods (Jominy test)
• EN 4258: General organization of metallic materials standardization for aerospace
• EN 4500-005: Rules for drafting and presenting standards for aerospace steels

These related European standards help ensure the quality, safety, and reliability demanded by the aerospace industry, supporting compliance and interoperability across international supply chains.

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By adhering to prEN 3523, organizations in the aerospace sector can achieve higher consistency in material properties, streamline certification, and reinforce safety-critical components in aircraft manufacturing. This standard, once finalized, will provide an essential reference for both steel producers and aerospace engineers throughout Europe and beyond.

SLOVENSKI STANDARD
01-april-2026
Aeronavtika - Jeklo 15CrMoV6 (1.7334) - Taljeno - Utrjeno in mehko žarjeno - Palice
za obdelavo - De ≤ 100 mm - 1080 MPa ≤ Rm ≤ 1280 MPas
Aerospace series - Steel 15CrMoV6 (1.7334) - Air melted - Hardened and tempered -
Bars for machining - De ≤ 100 mm - 1 080 MPa ≤ Rm ≤ 1 280 MPas
Luft- und Raumfahrt - Stahl 15CrMoV6 (1.7334) - Lufterschmolzen - Gehärtet und
angelassen - Stangen zur spanenden Bearbeitung - De ≤ 100 mm - 1 080 MPa ≤ Rm ≤ 1
280 MPa
Série aérospatiale - Acier 15CrMoV6 (1.7334) - Élaboré à l'air - Trempé et revenu -
Barres pour usinage - De ≤ 100 mm - 1 080 MPa ≤ Rm ≤ 1 280 MPa
Ta slovenski standard je istoveten z: prEN 3523
ICS:
49.025.10 Jekla Steels
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

DRAFT
EUROPEAN STANDARD
NORME EUROPÉENNE
EUROPÄISCHE NORM
February 2026
ICS 49.025.10 Will supersede EN 3523:2024
English Version
Aerospace series - Steel 15CrMoV6 (1.7334) - Air melted -
Hardened and tempered - Bars for machining - De  100
mm - 1 080 MPa  Rm  1 280 MPas
Série aérospatiale - Acier 15CrMoV6 (1.7334) - Élaboré Luft- und Raumfahrt - Stahl 15CrMoV6 (1.7334) -
Lufterschmolzen - Gehärtet und angelassen - Stangen
à l'air - Trempé et revenu - Barres pour usinage - De 
zur spanenden Bearbeitung - De  100 mm - 1 080 MPa
100 mm - 1 080 MPa  Rm  1 280 MPa
 Rm  1 280 MPa
This draft European Standard is submitted to CEN members for enquiry. It has been drawn up by the Technical Committee ASD-
STAN.
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
© 2026 CEN All rights of exploitation in any form and by any means reserved Ref. No. prEN 3523:2026 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 (prEN 3523:2026) 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 is currently submitted to the CEN Enquiry.
This document will supersede EN 3523:2024.
...