SCM440
Data verifiedSCM440 is the JIS Cr-Mo steel matching 4140/42CrMo4 — the designation on Japanese, Korean and Taiwanese certificates for the same class of machinery steel.
Chemical composition
| Element | Content (%) |
|---|---|
| C | 0.38–0.43 |
| Si | 0.15–0.35 |
| Mn | 0.60–0.90 |
| Cr | 0.90–1.20 |
| Mo | 0.15–0.30 |
Weight percent, per the governing standard ranges. Actual values per heat are on the mill certificate.
Properties
| Hardness (Q&T) | 28–38 HRC typical |
| Tensile strength | ≥980 MPa (Q&T reference) |
| Density | 7.85 g/cm³ |
Heat treatment
Quench 850 °C oil; temper 550–650 °C.
Equivalent grades
| Standard | Designation |
|---|---|
| din | 1.7225 (42CrMo4) |
| aisi | 4140 |
| jis | SCM440 |
| gb | 42CrMo |
Compare side by side: SCM440 vs 4140 · SCM440 vs 42CrMo4
Equivalents overlap in chemistry and use but are not always identical — see our equivalents guide before substituting in certified designs.
Applications & Processing
Applications: Shafts, gears, bolts, machine components across Asian supply chains.
Processing: As 4140/42CrMo4.
FAQ
- Can SCM440 replace 42CrMo4 on an EN drawing?
- Composition and properties overlap; with a 3.1 certificate showing EN-comparable values, substitution is commonly accepted — confirm with the design authority for certified parts.
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Ask for a quotationVisit NasteelSource: JIS G4105 published ranges · Last updated 2026-11-03. Data is indicative — verify critical values against the governing standard and mill certificate before use.
