EN 3677:2025

Aerospace series - Steel X5CrNiCu17-4 (1.4542) - Air melted - Solution treated and precipitation treated - Forgings - a or D ≤ 200 mm - Rm ≥ 1 310 MPa

This document specifies the requirements relating to:
Steel X5CrNiCu17-4 (1.4542)
Air melted
Solution treated and precipitation treated
Forgings
a or D ≤ 200 mm
Rm ≥ 1 310 MPa
for aerospace applications.
W.nr: 1.4542.
ASD-STAN: FE-PM3801.

Luft- und Raumfahrt - Stahl X5CrNiCu17-4 (1.4542) - Lufterschmolzen - Lösungsgeglüht und ausscheidungsgehärtet - Schmiedestücke - a oder D ≤ 200 mm - Rm ≥ 1 310 MPa

No Scope available

Série aérospatiale - Acier X5CrNiCu17-4 (1.4542) - Élaboré à l'air - Mis en solution et précipité - Pièces forgées ou matricées - a ou D ≤ à 200 mm - Rm ≥ à 1 310 Mpa

Le présent document spécifie les exigences relatives à :
Acier X5CrNiCu17-4 (1.4542)
Élaboré à l'air
Mis en solution et précipité
Pièces forgées ou matricées
a ou D ≤ 200 mm
Rm ≥ 1 310 MPa
pour les applications aérospatiales.
W.nr : 1.4542.
ASD-STAN : FE-PM3801.

Aeronavtika - Jeklo X5CrNiCu17-4 (1.4542) - Taljeno - Topilno žarjeno in izločevalno utrjeno - Izkovki - a ali D ≤ 200 mm - Rm ≥ 1310 MPa

General Information

• Status: Published
• Publication Date: 02-Dec-2025
• ICS: 49.025.10 - Steels
• 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: 03-Dec-2025
• Completion Date: 03-Dec-2025
• Ref Project: SIST EN 3677:2026 - Aerospace series - Steel X5CrNiCu17-4 (1.4542) - Air melted - Solution treated and precipitation treated - Forgings - a or D ≤ 200 mm - Rm ≥ 1 310 MPa

Relations

• Replaces: EN 3677:2007 - Aerospace series - Steel FE-PM3801 (X5CrNiCu17-4) - Air melted - Solution treated and precipitation treated - Forgings - a or D ≤ 200 mm - Rm ≥ 1 310 MPa
• Effective Date: 19-Jan-2023

Overview

EN 3677:2025 is a European standard developed by CEN that specifies the stringent requirements for Steel X5CrNiCu17-4 (1.4542) used in aerospace applications. This standard applies specifically to air melted forgings with dimensions a or D ≤ 200 mm and a minimum tensile strength (Rm) of 1,310 MPa. The steel undergoes solution treatment and precipitation treatment to meet its mechanical and microstructural criteria, ensuring it is suitable for high-performance aerospace components. This latest edition supersedes EN 3677:2007, incorporating updates on material designation, format corrections, and additional normative references.

Key Topics

• Material Specification
  The standard defines Steel X5CrNiCu17-4 (1.4542), which is air melted and supplied as forgings. It details chemical composition limits for elements including carbon, silicon, manganese, phosphorus, sulfur, chromium, molybdenum, nickel, copper, niobium, and tantalum.

• Heat Treatment
  Steel is solution treated at 1,025–1,055 °C for at least 30 minutes followed by air cooling, and precipitation treated between 470–490 °C for at least one hour. This treatment ensures the steel achieves the necessary mechanical properties, including minimum tensile strength and proof stress.

• Mechanical Properties
  The standard mandates:

  • Minimum tensile strength (Rm) ≥ 1,310 MPa
  • Proof stress (Rp0.2) ≥ 1,170 MPa
  • Minimum elongation and reduction of area values depending on forging size
  • Hardness range to maintain durability and resistance

• Testing and Inspection
  EN 3677:2025 references several aerospace standards for testing, such as ultrasonic inspection (EN 4050-4), visual testing (VT), micrographic analysis (EN 2951), and other procedures to detect imperfections and ensure batch uniformity.

• Dimensional Limits
  Forgings covered by this standard have dimensions with a or D ≤ 200 mm, allowing for precise control over product geometry in aerospace manufacturing.

Applications

EN 3677:2025 steel forgings are designed for critical aerospace components where high strength, corrosion resistance, and toughness are essential. Typical uses include:

• Structural aircraft parts requiring superior fatigue resistance
• Engine components exposed to high mechanical and thermal stresses
• Landing gear and other safety-critical assemblies
• Components demanding consistent microstructure and mechanical performance from the solution and precipitation treated steel

The standard helps aerospace manufacturers comply with uniform quality and safety requirements critical in the aerospace sector, ensuring reliability and performance in demanding environments.

Related Standards

EN 3677:2025 integrates with several other aerospace material standards to form a comprehensive framework for metallic materials:

• EN 4258 – General organization of standardization for aerospace metallic materials
• EN 4500-005 – Specific rules for drafting steel material standards in aerospace series
• EN 2951 – Micrographic determination of non-metallic inclusions
• EN 3163 – Specifications for air melted, softened forging stock of the same steel
• EN 4050-4 – Ultrasonic inspection methods and acceptance criteria
• EN 4700-006 – Technical specifications relating to steel forgings and wrought products

Compliance with these standards supports full traceability, quality control, and manufacturing best practices for aerospace-grade steel components.

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Keywords: EN 3677:2025, Steel X5CrNiCu17-4, aerospace steel standard, air melted steel forgings, solution treated steel, precipitation treatment, aerospace forgings, mechanical properties aerospace steel, steel tensile strength aerospace, CEN aerospace standards

Standards Content (Sample)

SLOVENSKI STANDARD
01-februar-2026
Aeronavtika - Jeklo X5CrNiCu17-4 (1.4542) - Taljeno - Topilno žarjeno in
izločevalno utrjeno - Izkovki - a ali D ≤ 200 mm - Rm ≥ 1310 MPa
Aerospace series - Steel X5CrNiCu17-4 (1.4542) - Air melted - Solution treated and
precipitation treated - Forgings - a or D ≤ 200 mm - Rm ≥ 1 310 MPa
Luft- und Raumfahrt - Stahl X5CrNiCu17-4 (1.4542) - Lufterschmolzen - Lösungsgeglüht
und ausscheidungsgehärtet - Schmiedestücke - a oder D ≤ 200 mm - Rm ≥ 1 310 MPa
Série aérospatiale - Acier X5CrNiCu17-4 (1.4542) - Élaboré à l'air - Mis en solution et
vieilli - Pièces forgées et pièces matricées - a ou D ≤ à 200 mm - Rm ≥ à 1 310 Mpa
Ta slovenski standard je istoveten z: EN 3677:2025
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 3677
EUROPEAN STANDARD
NORME EUROPÉENNE
December 2025
EUROPÄISCHE NORM
ICS 49.025.10 Supersedes EN 3677:2007
English Version
Aerospace series - Steel X5CrNiCu17-4 (1.4542) - Air
melted - Solution treated and precipitation treated -
Forgings - a or D  200 mm - Rm  1 310 MPa
Série aérospatiale - Acier X5CrNiCu17-4 (1.4542) - Luft- und Raumfahrt - Stahl X5CrNiCu17-4 (1.4542) -
Élaboré à l'air - Mis en solution et précipité - Pièces Lufterschmolzen - Lösungsgeglüht und
forgées ou matricées - a ou D  à 200 mm - Rm  à 1 ausscheidungsgehärtet - Schmiedestücke - a oder D 
310 Mpa
200 mm - Rm  1 310 MPa
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 3677:2025 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 3677:2025) 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 June 2026, and conflicting national standards shall be withdrawn at
the latest by June 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 3677:2007.
— update of the material designation;
— correction of the format of Table 1 to comply with the requirements of the EN 4500 series;
— update of Clause 2;
— addition of a bibliography.
According to the CEN-CENELEC Internal Regulations, the national standards organizations of the
following countries are bound to implement this document: Austria, Belgium, Bulgaria, Croati
...