SIST EN 4825:2021

Aerospace series - Steel X12CrNiMoV12-3 (1.4938) - Air melted and consumable electrode remelted - Hardened and tempered - Bars - De ≤ 150 mm - 900 MPa ≤ Rm ≤ 1 100 MPa

This document specifies the requirements relating to:
Steel X12CrNiMoV12-3 (1.4938)
Air melted and consumable electrode remelted
Hardened and tempered
Bars
De ≤ 150 mm
900 MPa ≤ Rm ≤ 1 100 MPa
for aerospace applications.

Luft- und Raumfahrt - Stahl X12CrNiMoV12-3 (1.4938) - Lufterschmolzen und mit selbstverzehrender Elektrode umgeschmolzen - Gehärtet- und angelassen - Stangen - De ≤ 150 mm - 900 MPa ≤ Rm ≤ 1 100 MPa

Dieses Dokument legt die Anforderungen an:
Stahl X12CrNiMoV12 3 (1.4938)
Lufterschmolzen und mit selbstverzehrender Elektrode umgeschmolzen
Gehärtet und angelassen
Stangen
De ≤ 150 mm
900 MPa ≤ Rm ≤ 1 100 MPa
für Anwendungen in der Luft  und Raumfahrt fest.

Série aérospatiale - Acier X12CrNiMoV12-3 (1.4938) - Élaboré à l'air et refondu à l'électrode consommable - Trempé et revenu - Barres - De ≤ 150 mm - 900 MPa ≤ Rm ≤ 1 100 MPa

Aeronavtika - Jeklo X12CrNiMoV12-3 (1.4938) - Taljeno na zraku in pretaljeno s taljivo elektrodo - Utrjeno in mehko žarjeno - Palice - De ≤ 150 mm - 900 MPa ≤ Rm ≤ 1 100 MPa

General Information

• Status: Published
• Publication Date: 13-May-2021
• ICS: 49.025.10 - Steels
• ICS: 77.140.60 - Steel bars and rods
• Technical Committee: I13 - Imaginarni 13
• Current Stage: 6060 - National Implementation/Publication (Adopted Project)
• Start Date: 13-May-2021
• Due Date: 18-Jul-2021
• Completion Date: 14-May-2021
• Ref Project: EN 4825:2021 - Aerospace series - Steel X12CrNiMoV12-3 (1.4938) - Air melted and consumable electrode remelted - Hardened and tempered - Bars - De ≤ 150 mm - 900 MPa ≤ Rm ≤ 1 100 MPa

Overview - EN 4825:2021 (Aerospace steel X12CrNiMoV12-3 / 1.4938)

EN 4825:2021 is a CEN (Aerospace & Defence) material standard that specifies requirements for steel X12CrNiMoV12-3 (1.4938) supplied as hardened and tempered bars for aerospace use. It covers bars with external diameter De ≤ 150 mm produced by air melting and consumable electrode remelting, and defines mechanical, metallurgical and inspection criteria for a high‑strength alloy with nominal tensile strength in the range 900 MPa ≤ Rm ≤ 1 100 MPa.

Key topics and technical requirements

• Material designation: X12CrNiMoV12-3 (EN 1.4938) - high‑alloy steel with chromium, molybdenum, nickel and vanadium additions; typical chemistry includes ~11–12.5% Cr, 1.5–2.0% Mo, 2–3% Ni, C ≈ 0.08–0.15%, V ≈ 0.25–0.40% (Fe balance).
• Manufacturing: Air melted and consumable electrode remelted routes are required to achieve purity and soundness.
• Dimensions: Bars with De ≤ 150 mm.
• Heat treatment: Supplied hardened and tempered. Austenitizing range ~1 020–1 050 °C with subsequent tempering at ≥ 640 °C (per standard guidance).
• Mechanical properties:
  • Tensile strength Rm: 900–1 100 MPa
  • Proof stress Rp0.2: ≥ 750 MPa
  • Elongation A: ≥ 14% (A ≥ 10% if cold worked)
  • Reduction of area Z: ≥ 40%
  • Impact energy KV: ≥ 30 J at 20 °C (notch direction T)
  • Hardness: approximately HB 269–331
• Metallurgical and inspection controls:
  • Grain size: G ≥ 5 (with some G = 3 permitted)
  • Non‑metallic inclusion control: EN 2951 Category 3
  • Ultrasonic internal inspection: EN 4050‑4 Class 4
  • Dimensional, marking and other inspection per EN 4700‑002

Applications and who uses EN 4825:2021

• Intended for aerospace structural and mechanical components where high strength and toughness are required.
• Typical users:
  • Aerospace manufacturers and OEMs specifying material for safety‑critical parts
  • Metallurgical engineers and material procurement teams
  • Steel bar producers and heat‑treatment suppliers qualifying aerospace grades
  • Quality assurance and inspection departments performing acceptance testing
• Practical uses include high‑strength bars for components that require strict mechanical, microstructural and non‑destructive testing controls.

Related standards

• EN 4700‑002 (technical specification for steel bars)
• EN 2043 (qualification of semi‑finished products)
• EN 2951 (micrographic inclusion measurement)
• EN 4050‑4 (ultrasonic acceptance criteria)
• EN 4258, EN 4500‑005 (series organization and drafting rules)

Keywords: EN 4825:2021, X12CrNiMoV12-3, 1.4938, aerospace steel, hardened and tempered bars, 900 MPa, consumable electrode remelted, air melted, CEN.

Standards Content (Sample)

SLOVENSKI STANDARD
01-julij-2021
Aeronavtika - Jeklo X12CrNiMoV12-3 (1.4938) - Taljeno na zraku in pretaljeno s
taljivo elektrodo - Utrjeno in mehko žarjeno - Palice - De ≤ 150 mm - 900 MPa ≤ Rm
≤ 1 100 MPa
Aerospace series - Steel X12CrNiMoV12-3 (1.4938) - Air melted and consumable
electrode remelted - Hardened and tempered - Bars - De ≤ 150 mm - 900 MPa ≤ Rm ≤ 1
100 MPa
Luft- und Raumfahrt - Stahl X12CrNiMoV12-3 (1.4938) - Lufterschmolzen und mit
selbstverzehrender Elektrode umgeschmolzen - Gehärtet- und angelassen - Stangen -
De ≤ 150 mm - 900 MPa ≤ Rm ≤ 1 100 MPa
Série aérospatiale - Acier X12CrNiMoV12-3 (1.4938) - Élaboré à l'air et refondu à
l'électrode consommable - Trempé et revenu - Barres - De ≤ 150 mm - 900 MPa ≤ Rm ≤
1 100 MPa
Ta slovenski standard je istoveten z: EN 4825:2021
ICS:
49.025.10 Jekla Steels
77.140.60 Jeklene palice in drogovi Steel bars and rods
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EN 4825
EUROPEAN STANDARD
NORME EUROPÉENNE
May 2021
EUROPÄISCHE NORM
ICS 49.025.10
English Version
Aerospace series - Steel X12CrNiMoV12-3 (1.4938) - Air
melted and consumable electrode remelted - Hardened
and tempered - Bars - De ≤ 150 mm - 900 MPa ≤ Rm ≤ 1
100 MPa
Série aérospatiale - Acier X12CrNiMoV12-3 (1.4938) - Luft- und Raumfahrt - Stahl X12CrNiMoV12-3 (1.4938)
Élaboré à l'air et refondu à l'électrode consommable - - Lufterschmolzen und mit selbstverzehrender
Elektrode umgeschmolzen - Gehärtet- und angelassen -
Trempé et revenu - Barres - De ≤ 150 mm - 900 MPa ≤
Stangen - De ≤ 150 mm - 900 MPa ≤ Rm ≤ 1 100 MPa
Rm ≤ 1 100 MPa
This European Standard was approved by CEN on 18 January 2021.

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,
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United Kingdom.
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EUROPÄISCHES KOMITEE FÜR NORMUNG

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© 2021 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN 4825:2021 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 4825:2021) has been prepared by the Aerospace and Defence Industries
Association of Europe — Standardization (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, 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 November 2021, and conflicting national standards shall be
withdrawn at the latest by November 2021.
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.
According to the CEN-CENELEC Internal Regulations, the national standards organizations of the
following countries are bound to implement this document: Austria, Belgium, Bulgaria, Croatia,
Cyprus, Czech Repu
...