EN24 (817M40T)

High tensile steel

EN24 | 817M40T | 34CrNiMo6 Engineering steel

EN24 | 817M40T | 34CrNiMo6 is a high-strength alloy steel designed for applications requiring exceptional toughness, fatigue resistance and performance under high loads. Supplied as black flat bar, EN24 is commonly used in precision engineering where reliability is critical.

The EN24 steel grade is a nickel chromium molybdenum combination, hence the European grade 34CrNiMo6. EN24 offers high tensile steel strength, with good ductility and wear resistance characteristics. With relatively good impact properties at low temperatures, EN24 is also suitable for a variety of raised temperature applications.

EN24 Engineering Steel is easy to treat and temper and is supplied hardened and tempered. The alloy offers a good combination of strength, ductility and wear resistance. It is a very high strength alloy engineering steel.

EN24 steel is the ideal choice for sub-contract engineers working to tight tolerances and performance specifications.

Key properties of EN24

  • Very high tensile strength
  • Excellent fatigue resistance
  • Superior toughness
  • Good wear resistance
  • Stable under heavy load conditions

Milling benefits for EN24 flat bar

Milling EN24 improves machining reliability. This is key when working with high-value components.

  • Increased dimensional consistency
  • Reduced distortion during machining
  • Improved surface condition
  • Better repeatability for production runs

Steel stock range

High Peak Steels stock EN24 | 817M40T | 34CrNiMo6 in black steel round, square & flat bar and bright steel round bar . EN24 is also available in forged block form that we can cold saw to size.

Associated standards

UK Standard EN24 | European Grade 34CrNiMo6 | Werkstoff 1.6565, 1.6582 | SAE/AISI 4340

What is EN24 steel used for?

EN24 is used for high-performance components such as heavy-duty shafts and gears where strength and fatigue resistance are critical.

Is EN24 stronger than EN19?

Yes, EN24 generally offers greater toughness and fatigue resistance, making it suitable for more demanding applications.

Is EN24 suitable for precision machining?

Yes, EN24 is widely used in precision engineering, especially when supplied in a consistent and machined condition.

EN24 availability

EN24 prices and stock

Typical Applications for EN24

EN24 is used in demanding engineering environments such as:

  • High-load shafts
  • Heavy-duty gears
  • Precision machined components
  • Repetition parts under stress
For a balance of strength and cost consider using EN19 steel as an alternative to EN24
For general engineering applications consider using EN9 steel as an alternative to EN24

EN24 | 817M40T | 34CrNiMo6 black steel

Shapes & sizes

ProductMin sizeMax size
codes-round240mm dia500mm dia
codes-flat220mm x 10mm900mm x 300mm
codes-square225mm150mm
codes-hex2

EN24 | 817M40T | 34CrNiMo6 bright mild steel

Shapes & sizes

ProductMetric sizes
Min
Max		Imperial sizes
Min
Max
codes-round210mm dia75mm dia1/2" dia3" dia
codes-flat2
codes-square2
codes-hex2

EN24 | 817M40T | 34CrNiMo6 Chemical Composition

CSiMnSPCrNiMo
Min0.360.10.4511.30.2
Max0.440.350.70.040.0351.41.70.35

EN24 | 817M40T | 34CrNiMo6 Mechanicals

Yield
N/mm2		0.2% proof
N/mm2		UTS (Rm)
N/mm2		Elong (A)
%		Red of Area (Z)
%		Hardness
HB		Impact Test (KV)
J
Quenched & Tempered to condition T (min)
6808501324850
Quenched & Tempered to condition T (max)
1000302
Quenched & Tempered to condition U (min)
7559251226942
Quenched & Tempered to condition U (max)
1075331
Quenched & Tempered to condition V (min)85010001229342
Quenched & Tempered to condition V (min)85011501229342
Drawn Quenched & Tempered to condition T (min)700850924850
Drawn Quenched & Tempered to condition T (max)1000302

For more information on EN24 high tensile steel Please get in touch

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