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.
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 values for a reference section and heat-treatment condition. Actual properties vary with dimension and treatment, and are confirmed on the mill certificate.
Available forms.
Size: Ø 8 – 800 mm · flats, plates & sheet to specification
Typical applications.
- Crankshafts
- Axles & drive shafts
- Gears & pinions
- Hydraulic components
- High-stress machine parts
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 and 4140, SCM440, 708M40 are matching designations for the same steel across different standards (EN, AISI/SAE, JIS, GB, former DIN). They are near equivalents and may differ slightly in chemistry, so 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 (bar diameter; flats, plates and sheet are quoted to specification).
What is 42CrMo4 used for?
Typical applications include Crankshafts, Axles & drive shafts, Gears & pinions, Hydraulic components, High-stress machine parts.