Alloy Steel

42CrMo4 · 1.7225

Also known as 4140 / SCM440 / 708M40

Chromium-molybdenum engineering steel for high-stress shafts, gears and crankshafts.

42CrMo4 (material 1.7225, equivalent to AISI 4140) is a low-alloy chromium-molybdenum engineering steel valued for its high strength, toughness and good hardenability in the quenched-and-tempered condition. One of the most widely used grades for highly stressed machine and automotive components, available hot-rolled, cold-drawn (bright) and forged.

International equivalents.

The same steel by country and standard — near matches; mill certificate governs.

42CrMo4 (1.7225) · EN 4140 · AISI / SAE SCM440 · JIS 42CrMo · GB 708M40 · BS

Chemical composition.

Indicative, % by weight per EN 10083-3. Mill certificate governs.

Element%
C 0.38 – 0.45
Si ≤ 0.40
Mn 0.60 – 0.90
Cr 0.90 – 1.20
Mo 0.15 – 0.30
P ≤ 0.025
S ≤ 0.035

Mechanical properties.

Indicative; depends on dimension and heat treatment.

Tensile strength (Rm)
900 – 1100 MPa (Q+T)
Yield strength (Re)
≥ 650 MPa
Elongation (A)
≥ 12 %
Hardness (annealed)
≤ 241 HB

Available forms.

Round bar Flat bar Bright / cold-drawn bar Forged

Size range: Ø 8 – 800 mm

Typical applications.

  • Crankshafts
  • Axles & drive shafts
  • Gears & pinions
  • Hydraulic components
  • High-stress machine parts
Standards: EN 10083-3EN 10250-3

FAQ.

What is 42CrMo4?

42CrMo4 (material 1.7225, equivalent to AISI 4140) is a low-alloy chromium-molybdenum engineering steel valued for its high strength, toughness and good hardenability in the quenched-and-tempered condition. One of the most widely used grades for highly stressed machine and automotive components, available hot-rolled, cold-drawn (bright) and forged.

Is 42CrMo4 the same as 4140?

Yes — 42CrMo4 is the European (EN) designation, while 4140, SCM440, 708M40 are the matching names used in other countries and standards (for example AISI/SAE in the USA, JIS in Japan, GB in China, former DIN in Germany). They are near equivalents and may differ slightly in chemistry; the mill certificate governs the exact specification.

What are the international equivalents of 42CrMo4?

42CrMo4 corresponds to 42CrMo4 (1.7225) (EN), 4140 (AISI / SAE), SCM440 (JIS), 42CrMo (GB), 708M40 (BS). Equivalents are nearest matches by country/standard; the mill certificate governs the exact specification.

In which forms is 42CrMo4 available?

42CrMo4 is supplied as Round bar, Flat bar, Bright / cold-drawn bar, Forged, in Ø 8 – 800 mm.

What is 42CrMo4 used for?

Typical applications include Crankshafts, Axles & drive shafts, Gears & pinions, Hydraulic components, High-stress machine parts.