SCM430 vs SCM435
These two grades are listed as equivalents of each other: their chemistry windows overlap and they serve the same applications. They are not always identical — check the differences below before substituting, especially in certified designs.
SCM430
Alloy & Engineering Steel
SCM430 is the JIS G4053 chromium-molybdenum machine structural steel corresponding to AISI 4130, with a slightly higher manganese and chromium window in the JIS specification. It is one of the most traded alloy round bars in Japan and Southeast Asia for shafts, bolts and hydraulic components.
Standards: DIN 25CrMo4 / 1.7218 (near) · AISI 4130 · JIS SCM430 (JIS G4053) · GB 30CrMo (near)
SCM435
Alloy & Engineering Steel
SCM435 is the JIS Cr-Mo through-hardening steel matching AISI 4135 and EN 34CrMo4 — one step below SCM440/4140 in carbon, with slightly easier welding and machining at nearly the same Q&T strength level. It is a staple of Japanese bolt, shaft and machinery production.
Standards: DIN 1.7220 (34CrMo4) · AISI 4135 · JIS SCM435 (JIS G4053) · GB 35CrMo
Chemical composition compared (%)
| Element | SCM430 | SCM435 |
|---|---|---|
| C | 0.28–0.33 | 0.33–0.38 |
| Si | 0.15–0.35 | 0.15–0.35 |
| Mn | 0.60–0.85 | 0.60–0.90 |
| P | ≤0.030 | ≤0.030 |
| S | ≤0.030 | ≤0.030 |
| Cr | 0.90–1.20 | 0.90–1.20 |
| Mo | 0.15–0.30 | 0.15–0.30 |
Properties compared
| Property | SCM430 | SCM435 |
|---|---|---|
| Tensile strength | ≥830 MPa (Q&T reference) | ≥930 MPa (Q&T reference) |
| Yield strength | ≥685 MPa (Q&T reference) | ≥785 MPa (Q&T reference) |
| Density | 7.85 g/cm³ | 7.85 g/cm³ |
| Hardness (Q&T) | — | 28–38 HRC typical |
Sourcing either grade?
Nasteel stocks both families from Shenzhen with EN 10204 3.1 mill certificates by heat number.
Ask for a quotationSee full data sheets: SCM430 · SCM435. Substitution decisions for certified parts stay with the design authority.