Description
65Mn Steel Introduction:
65Mn is a high-carbon, manganese-rich spring steel known for its excellent strength, hardness, and wear resistance. This steel is commonly used in applications requiring high tensile strength and elasticity, such as in automotive components, machinery, and various spring applications. The manganese content improves the steel’s hardenability and toughness, making it suitable for heavy-duty and high-stress environments.
65Mn Grade Applications:
65Mn is typically used for:
- Leaf springs
- Coil springs
- Automotive suspension components
- Machinery parts
- High-strength fasteners
- Cutting tools
Equivalent Grades:
- GB: 65Mn
- DIN: 1.1191
- AISI/SAE: 9265 (similar)
- JIS: SUP9 (comparable)
Chemical Composition:
| Element | Content (%) |
|---|---|
| C | 0.60-0.67 |
| Mn | 0.90-1.20 |
| P | ≤ 0.035 |
| S | ≤ 0.035 |
| Si | ≤ 0.35 |
Mechanical Properties:
| Property | Value |
|---|---|
| Tensile strength (MPa) | 1000-1300 |
| Yield strength (MPa) | ≥ 850 |
| Elongation rate (%) | ≥ 10 |
| Reduction of area (%) | ≥ 30 |
| Hardness (HB) | 250-330 (quenched and tempered) |
65Mn Hardness:
In its quenched and tempered condition, 65Mn typically has a hardness range of 250 to 330 HB. After heat treatment, the hardness can reach 45-55 HRC, depending on the quenching and tempering parameters.
Heat Treatment:
65Mn undergoes various heat treatments to optimize its hardness, strength, and durability.
Hardening Process:
- Heating for hardening: Heat the steel to 850-900°C, then quench in oil or water.
- Tempering: Tempering is carried out at 400-600°C to improve toughness and relieve internal stresses while maintaining desired hardness.
Physical Properties:
| Property | Value |
|---|---|
| Modulus of Elasticity (N/mm²) | 210 × 10³ |
| Density (g/cm³) | 7.85 |
| Thermal Conductivity (W/m.K) | 45.0 |
Thermal Properties:
- Thermal conductivity: 45.0 W/m.K at room temperature.
- Specific heat: 460 J/kg-K.
Forging Properties:
65Mn can be forged at temperatures between 1100°C and 850°C. After forging, the material should be cooled slowly to minimize internal stresses and prevent cracking.
Normalizing:
Normalizing is performed at 850-880°C, followed by air cooling. This process improves the grain structure, enhancing the steel’s toughness and strength.
Annealing:
Annealing is typically done at 780-820°C, followed by slow cooling. This softens the material to facilitate machining and forming before final heat treatment.
Welding:
65Mn is generally not recommended for welding due to its high carbon content, which can lead to cracking and other issues. If welding is required, preheating and post-weld heat treatment are essential to mitigate these risks.
Supply Cities:
Mumbai Ahmedabad, Amaravathi, Ambattur, Bangalore, Belgaum, Chennai, Chittoor, Coimbatore, Dindigul, Mysore, Nellore, Hyderabad, Kochi, Mangalore, Tirupur, Tuticorin, Madurai, Andhra Pradesh, Karnataka, Puducherry, Kerala, Tamil Nadu, Telangana, Visakhapatnam, Kochi, Kerala, Hubli-Dharwad, Karnataka, Ghaziabad Kolkata.
