Description
30CrMnSiA Alloy Steel Overview
30CrMnSiA is a high-strength, low-alloy structural steel primarily known for its exceptional mechanical properties, including high strength, toughness, and excellent wear resistance. It is a Cr-Mn-Si alloy steel, where chromium improves wear resistance, manganese increases strength and toughness, and silicon contributes to hardenability and corrosion resistance. This alloy steel is widely used in the manufacturing of critical structural components that require high mechanical performance under stressful conditions. It is favored in industries such as aerospace, military, and machinery manufacturing due to its versatility and adaptability to heat treatment.
Key Features of 30CrMnSiA:
- High Strength: This alloy offers excellent tensile and yield strength, suitable for high-stress applications.
- Good Toughness: Resistant to fracture and cracks under heavy loads.
- Wear Resistance: Chromium content improves the steel’s durability against wear and tear.
- Excellent Hardenability: Silicon enhances hardenability, making the alloy suitable for heat treatment.
- Weldability: Suitable for welding with proper preheating and post-weld heat treatment to avoid cracking.
Applications of 30CrMnSiA Alloy Steel
30CrMnSiA is extensively used in industries that require components to withstand high levels of stress, wear, and impact. Its key applications include:
- Aerospace Industry: For manufacturing aircraft structural components, landing gear parts, and high-stress frames.
- Military Equipment: Used in the production of tanks, armored vehicles, and missile parts.
- Automotive Industry: Applied in gears, shafts, and other heavy-duty automotive components.
- Machinery Manufacturing: Gears, crankshafts, and various mechanical parts that require high toughness and wear resistance.
Equivalent Grades for 30CrMnSiA
The 30CrMnSiA steel has several international equivalents. These equivalent grades help in finding similar materials across different countries.
| Standard | Equivalent Grade |
|---|---|
| GB (China) | 30CrMnSiA |
| AISI/SAE | 4130 (approximate) |
| DIN | 1.7216 |
| JIS (Japan) | SCM430 |
| UNS | G41300 |
Chemical Composition of 30CrMnSiA
The chemical composition of 30CrMnSiA alloy steel is designed to provide a balanced combination of strength, toughness, and wear resistance. Below is the typical chemical composition:
| Element | Composition (%) |
|---|---|
| Carbon (C) | 0.28 – 0.34 |
| Silicon (Si) | 0.90 – 1.20 |
| Manganese (Mn) | 0.80 – 1.10 |
| Phosphorus (P) | 0.030 max |
| Sulfur (S) | 0.030 max |
| Chromium (Cr) | 0.80 – 1.10 |
This chemical composition contributes to the steel’s high tensile strength, good wear resistance, and improved hardenability.
Mechanical Properties of 30CrMnSiA
The mechanical properties of 30CrMnSiA alloy steel make it suitable for high-performance applications, especially in environments requiring both strength and toughness. The typical values for these properties are:
| Property | Value |
|---|---|
| Tensile Strength (MPa) | 980 – 1180 |
| Yield Strength (MPa) | 835 – 1030 |
| Elongation (%) | 10 – 16 |
| Reduction in Area (%) | 40 – 50 |
| Impact Toughness (J) | ≥ 39 (at 20°C) |
| Hardness (HB, annealed) | 217 – 255 |
Heat Treatment of 30CrMnSiA
Heat treatment is essential to optimize the mechanical properties of 30CrMnSiA. Various heat treatment processes can be applied to enhance its performance in specific applications.
- Annealing: Heat to 860 – 880°C, hold for a sufficient period, and cool slowly. Annealing helps in refining the grain structure and improving machinability.
- Quenching: Quench from 880 – 920°C in water or oil, followed by tempering. This increases strength and hardness.
- Tempering: Temper at 500 – 700°C to reduce brittleness and improve toughness.
Hardness of 30CrMnSiA
The hardness of 30CrMnSiA alloy steel varies based on its heat treatment condition. In the annealed condition, the typical hardness ranges between 217 – 255 HB. After quenching and tempering, the hardness can reach values between 300 – 350 HB.
Physical Properties of 30CrMnSiA
The physical properties of 30CrMnSiA alloy steel are also notable and contribute to its effectiveness in demanding applications:
| Property | Value |
|---|---|
| Density (g/cm³) | 7.85 |
| Thermal Conductivity (W/m·K) | 42 – 48 |
| Specific Heat Capacity (J/kg·K) | 460 – 500 |
| Electrical Resistivity (µΩ·cm) | 19.0 |
| Melting Point (°C) | 1420 – 1460 |
Forging Properties of 30CrMnSiA
30CrMnSiA is highly suitable for forging. The recommended forging temperature range is 1150 – 850°C. After forging, components should be cooled slowly to relieve internal stresses and prevent cracking.
Stress Relieving for 30CrMnSiA
Stress relieving is recommended to eliminate residual stresses generated by machining or forming. Heat the steel to 600 – 650°C, hold for 1-2 hours, and cool slowly.
Normalizing 30CrMnSiA
Normalizing is conducted by heating the steel to 880 – 920°C, followed by air cooling. This process improves grain structure and refines mechanical properties.
Annealing 30CrMnSiA
Annealing is performed at 860 – 880°C, followed by slow cooling in the furnace. Annealing enhances the steel’s machinability and reduces internal stresses.
Machinability of 30CrMnSiA
30CrMnSiA alloy steel offers good machinability, especially in the annealed or normalized condition. High-speed tools and appropriate cutting parameters are recommended for efficient machining.
Welding of 30CrMnSiA
Welding 30CrMnSiA is possible, but precautions are necessary to avoid cracking. Preheating the steel to 150 – 300°C and post-weld heat treatment is recommended to restore the steel’s mechanical properties and avoid stress-induced cracking.
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.
