Description
45C8 Grade Introduction:
45C8 Carbon Steel is a medium carbon steel with carbon as the primary alloying element. It contains up to 0.4% silicon and 1.2% manganese along with small amounts of residual elements such as copper, molybdenum, aluminum, chromium, and nickel. This steel grade is ideal for applications requiring good hardness, strength, and toughness.
45C8 Grade Application:
45C8 steel is widely used in the production of axles, bolts, forged connecting rods, crankshafts, torsion bars, light gears, screws, guide rods, sickles, axes, knives, woodworking drills, hammers, and other forging parts.
45C8 Equivalent Grades:
| Standard | Equivalent Grades |
|---|---|
| EN | EN8, EN8A, EN8B, EN8C, EN8D |
| BS | 080A40 |
| DIN | CK45 |
| AISI | 1040, 1045 |
Additional Grades Available:
In addition to 45C8, we also supply EN1A, EN8, EN24, EN31, D2, H11, H13, SCM420, and other carbon and alloy steels.
45C8 Chemical Composition:
| Element | C | Mn | Si | S (Max) | P (Max) |
|---|---|---|---|---|---|
| Content | 0.43 | 0.74 | 0.22 | 0.023 | 0.030 |
45C8 Mechanical Properties:
| Property | Metric | Imperial |
|---|---|---|
| Tensile Strength Ultimate | 660 MPa | 95,700 psi |
| Tensile Strength Yield | 560 MPa | 81,200 psi |
| Bulk Modulus | 140 GPa | 20,300 ksi |
| Shear Modulus | 80 GPa | 11,600 ksi |
| Elastic Modulus | 190-210 GPa | 19,700-30,458 ksi |
| Poisson’s Ratio | 0.27-0.30 | 0.27-0.30 |
| Elongation at Break (in 50 mm) | 0.1 | 0.1 |
| Reduction of Area | 0.4 | 0.4 |
| Hardness (Brinell) | 197 | 197 |
| Machinability | 55% | 55% |
45C8 Hardness:
The Brinell hardness of 45C8 is approximately 197 HBW.
45C8 Heat Treatment:
- Hardening: Heat to 820-860°C, followed by quenching in water or oil.
- Tempering: Temper at 550-660°C in air.
45C8 Physical Properties:
| Property | Metric | Imperial |
|---|---|---|
| Density | 7.85 g/cm³ | 0.284 lb/in³ |
45C8 Thermal Properties:
| Property | Metric | Imperial |
|---|---|---|
| Thermal Expansion Coefficient | 11 µm/m°C | 6.11 µin/in°F |
| Thermal Conductivity | 49.8 W/mK | 346 BTU in/hr.ft².°F |
45C8 Forging Properties:
Forging is performed between 1100°C and 850°C, followed by air cooling.
45C8 Stress Relieving:
Stress relieving may be necessary to reduce internal stresses from welding or machining.
45C8 Normalizing:
Normalize by heating to 840-880°C, followed by air cooling.
45C8 Annealing:
Anneal the steel by heating to 680-710°C, followed by slow furnace cooling.
45C8 Machinability:
Machinability of 45C8 steel is good, with a rating of 55% compared to AISI 1212 steel.
45C8 Welding:
Welding of 45C8 is possible, but it is essential to control cooling rates to avoid cracking. After welding, components should cool to 180°C before tempering. Post-weld heat treatment at 620-650°C for 2 hours is recommended to relieve stress.
45C8 Alternative Welding Procedure:
If immediate tempering isn’t feasible, preheat to 250°C and hold for 4 hours minimum before cooling. Afterward, temper the component when convenient to avoid hydrogen-induced cracking.
