4130
Data verified4130 is a low-alloy Cr-Mo steel famous for weldable high strength in tube form — aircraft structures, racing chassis, bicycle frames and oilfield parts.
Chemical composition
| Element | Content (%) |
|---|---|
| C | 0.28–0.33 |
| Si | 0.15–0.35 |
| Mn | 0.40–0.60 |
| Cr | 0.80–1.10 |
| Mo | 0.15–0.25 |
Weight percent, per the governing standard ranges. Actual values per heat are on the mill certificate.
Properties
| Tensile strength | 560–670 MPa (annealed); 850–1000 MPa (normalized/Q&T) |
| Density | 7.85 g/cm³ |
| Weldability | Good (thin sections) |
Heat treatment
Normalize 870–900 °C; quench 850 °C oil/water; temper as required.
Equivalent grades
| Standard | Designation |
|---|---|
| din | 1.7218 (25CrMo4) |
| aisi | 4130 |
| jis | SCM430 |
| gb | 30CrMo |
Equivalents overlap in chemistry and use but are not always identical — see our equivalents guide before substituting in certified designs.
Applications & Processing
Applications: Aircraft tubing, roll cages, gun barrels, hydraulic line tubing, structural parts.
Processing: Excellent weldability in thin sections (TIG standard); commonly used normalized for welded structures.
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Ask for a quotationVisit NasteelSource: SAE J404 / ASTM A29 published ranges · Last updated 2026-11-03. Data is indicative — verify critical values against the governing standard and mill certificate before use.