S45C Carbon Steel Round Bar — Factory Direct Supplier | Huaxia-Steel
S45C is a medium-carbon steel defined by JIS G4051, widely used in machinery, automotive, and equipment manufacturing across Asia. With 0.42–0.48% carbon content, S45C offers an excellent balance of strength, toughness, and machinability — making it the go-to grade for shafts, gears, pins, and couplings.
Huaxia Steel supplies S45C round bar in as-rolled, annealed, and quenched-and-tempered (QT) conditions, with full JIS-compliant MTC documentation.
Product Specifications
Size Range
| Parameter | Range |
|---|---|
| Diameter | 6–300 mm |
| Length | 3–6 m (random) or fixed |
| Condition | As-rolled, annealed, QT, cold-drawn |
| Tolerance (hot-rolled) | ±0.5–1.0 mm (GB/T 702) |
| Tolerance (cold-drawn) | h9–h11 (ISO) |
| Tolerance (peeled) | h9, Ra 1.6–3.2 µm |
Chemical Composition (JIS G4051)
| Element | S45C (%) |
|---|---|
| C | 0.42–0.48 |
| Si | 0.15–0.35 |
| Mn | 0.60–0.90 |
| P | ≤0.030 |
| S | ≤0.035 |
| Ni | ≤0.20 |
| Cr | ≤0.20 |
| Cu | ≤0.30 |
| Fe | Balance |
Cross-Reference
| Standard | Equivalent |
|---|---|
| JIS G4051 | S45C |
| AISI/SAE | 1045 |
| GB/T 699 | 45# steel |
| DIN | 1.0503 (C45) |
| EN 10083-2 | C45E |
Mechanical Properties by Condition
| Condition | Yield (MPa) | Tensile (MPa) | Elong. (%) | Hardness (HB) | Typical Use |
|---|---|---|---|---|---|
| As-rolled | 310–380 | 565–700 | 12–16 | 170–220 | General machining |
| Annealed | 300–370 | 540–640 | 15–20 | 150–180 | Heavy machining |
| Normalized | 340–400 | 580–700 | 14–18 | 170–210 | Consistent properties |
| QT (550°C temper) | 550–700 | 750–900 | 12–16 | 220–270 | Shafts, gears |
| QT (400°C temper) | 650–800 | 850–1050 | 8–12 | 250–300 | High-stress parts |
Manufacturing Capabilities
| Service | Available | Description |
|---|---|---|
| Hot rolling | ✓ | 16–300 mm diameter |
| Cold drawing | ✓ | 6–80 mm diameter |
| Peeling | ✓ | 20–200 mm, surface Ra 1.6–3.2 |
| Centerless grinding | ✓ | 6–50 mm, tolerance h8/h9 |
| Heat treatment | ✓ | Annealing, normalizing, QT |
| Cutting | ✓ | Fixed length ±1 mm |
| Straightening | ✓ | ≤2 mm/m (precision), ≤4 mm/m (general) |
Quality Assurance
- **MTC per EN 10204 3.1** — full chemistry + mechanical properties
- **Hardness test** — Brinell (ASTM E10) or Rockwell (ASTM E18) at 2 locations per bar
- **UT testing** — per ASTM E213 (on request)
- **Dimensional inspection** — diameter, straightness, length
- **Microstructure** — tempered martensite for QT, pearlite+ferrite for annealed (on request)
FOB Pricing (2025–2026)
| Condition | Diameter (mm) | FOB ($/ton) | MOQ |
|---|---|---|---|
| As-rolled | 20–80 | 620–700 | 5 tons |
| Annealed | 20–80 | 660–760 | 5 tons |
| QT | 20–80 | 720–880 | 5 tons |
| Cold-drawn | 10–50 | 820–980 | 3 tons |
| Peeled | 20–80 | 780–920 | 3 tons |
| Centerless ground | 10–40 | 950–1200 | 2 tons |
FAQ
**Q: Is S45C the same as AISI 1045?**
A: Nearly identical. Both have 0.42–0.48% carbon. Minor differences exist in P/S limits (S45C is tighter). For most applications, they are interchangeable. Verify on the MTC.
**Q: What condition should I order for CNC machining?**
A: Annealed condition (150–180 HB) provides the best machinability and tool life. For shafts requiring surface hardness, order QT material (220–270 HB) and machine it, then induction-harden the surface.
**Q: Can you supply S45C with ultrasonic testing?**
A: Yes. We can supply UT-tested bar per ASTM E213 (Grade A/B/C). Add 3–5% to price and 3–5 days to lead time.
Get a Quote for S45C Round Bar
**[Contact Huaxia Steel →](https://www.huaxia-steel.com/contact/)** — specify diameter, condition, length, and quantity. We will confirm pricing, lead time, and MTC availability within 24 hours.
