SAE 1020 vs 1045
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.
SAE 1020
Carbon Steel
SAE 1020 is a low-carbon steel for general engineering: easily machined, formed and welded, and the default material for low-load shafts, pins and seamless tube in carbon grade.
Standards: DIN 1.0402 (C22) · AISI 1020 · JIS S20C · GB 20
1045
Carbon Steel
1045 is the world’s most common medium-carbon steel — the default for shafts, hydraulic rods and plates that need more strength than mild steel, with optional induction hardening.
Standards: DIN 1.0503 (C45) · AISI 1045 · JIS S45C · GB 45
Chemical composition compared (%)
| Element | SAE 1020 | 1045 |
|---|---|---|
| C | 0.18–0.23 | 0.43–0.50 |
| Mn | 0.30–0.60 | 0.60–0.90 |
| P | ≤0.040 | ≤0.040 |
| S | ≤0.050 | ≤0.050 |
| Si | — | 0.15–0.35 (typ.) |
Properties compared
| Property | SAE 1020 | 1045 |
|---|---|---|
| Tensile strength | 380–450 MPa (hot rolled) | 570–700 MPa (normalized) |
| Yield strength | ≥245 MPa | — |
| Density | 7.85 g/cm³ | 7.85 g/cm³ |
| Weldability | Excellent | — |
| Hardness | — | 170–210 HB (normalized); 50+ HRC surface by induction |
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: SAE 1020 · 1045. Substitution decisions for certified parts stay with the design authority.