S45C Material Detailed Information
S45C is a medium-carbon steel with good mechanical strength, machinability, and wear resistance. It is widely used in engineering, machinery, and mold applications where moderate strength and hardness are required.
S45C is equivalent to AISI 1045 (USA), DIN C45 (Germany), and JIS S45C (Japan), making it one of the most commonly used carbon steels for general engineering purposes.
Key Features
- Good Strength & Hardness: Can be surface-hardened for improved wear resistance.
- Excellent Machinability: Easily processed by cutting, drilling, and grinding.
- Moderate Wear Resistance: Can be improved with heat treatment.
- Good Weldability: Preheating is recommended to avoid cracking.
- Affordable & Widely Available: Commonly used in general engineering applications.
Chemical Composition
| Element | Composition (%) |
| Carbon (C) | 0.42 – 0.48 |
| Manganese (Mn) | 0.60 – 0.90 |
| Silicon (Si) | 0.15 – 0.35 |
| Phosphorus (P) | ≤ 0.030 |
| Sulfur (S) | ≤ 0.030 |
Mechanical Properties
| Property | Value |
| Hardness (Annealed) | ≤ 180 HB |
| Hardness (Hardened & Tempered) | 55-60 HRC (after surface hardening) |
| Tensile Strength | 570 – 700 MPa |
| Yield Strength | 300 – 500 MPa |
| Elongation | 10-16% |
| Impact Strength | Moderate |
S45C vs. 1045 vs. C45
| Property | S45C (JIS) | AISI 1045 (USA) | C45 (DIN) |
| Carbon Content | 0.42-0.48% | 0.43-0.50% | 0.42-0.50% |
| Strength | Moderate | Moderate | Moderate |
| Hardness (After Heat Treatment) | 55-60 HRC | 55-60 HRC | 55-60 HRC |
| Machinability | Good | Good | Good |
| Weldability | Moderate (preheating required) | Moderate | Moderate |
Applications
S45C is mainly used in mechanical and structural applications, including:
- Machine components (shafts, gears, spindles, axles)
- Automotive parts (connecting rods, crankshafts)
- Mold bases and mold holders
- Hydraulic and pneumatic cylinders
- General engineering structures
Heat Treatment Process
Annealing
Heat at 680–720°C, then slowly cool in the furnace
Normalizing
Heat to 850–900°C, then air cool
Hardening
Heat to 820–860°C, quench in water or oil
Tempering
Heat at 500–650°C to adjust hardness and toughness
Surface Hardening
Carburizing, induction hardening, or nitriding can improve wear resistance
Alternative Materials
- AISI 1045 – Equivalent American standard steel with similar properties
- C45 (DIN 1.1191) – European standard steel with slightly higher machinability
- SCM440 (AISI 4140) – An alloy steel with better strength and toughness
- S50C – A higher-carbon version with better hardness and wear resistance
Conclusion
S45C is a versatile and cost-effective medium-carbon steel with good strength, machinability, and wear resistance. It is widely used in mechanical parts, structural components, and mold bases.
