SAE/AISI 4820 Alloy Steel (UNS G48200)
SAE/AISI 4820 steel is a good choice for applications that require high strength and good hardenability. It is a versatile material that can be used in a variety of forms, including bars, plates, and forgings.
| Chemical Composition | ||
|---|---|---|
| Element | Min | Max |
| Iron | 94.645% | 95.72% |
| Carbon | 0.18% | 0.23% |
| Manganese | 0.50% | 0.70% |
| Molybdenum | 0.20% | 0.30% |
| Nickel | 3.25% | 3.75% |
| Phosphorous | 0.035% | |
| Silicon | 0.15% | 0.30% |
| Sulfur | 0.04% | |
The following table provides a list of SAE/AISI 4820 properties in both SI and US customary/Imperial units.
Click on the icon to switch between Metric and Imperial units.
| Physical Properties | Metric |
|---|---|
| Density | 7850 kg/m3 |
| Mechanical Properties | Metric |
| Tensile Strength (Ultimate) | 685 MPa |
| Tensile Strength (Yield) | 460 MPa |
| Young’s Modulus (E) | 190 - 210 GPa |
| Bulk Modulus (K) | 140 GPa |
| Shear Modulus (G) | 80 GPa |
| Poisson’s Ratio (ν) | 0.27 - 0.30 |
| Brinell Hardness | 197 |
| Thermal Properties | Metric |
| Thermal Conductivity | 44.5 W/m·K |
| Specific Heat Capacity (Cp) | 470 J/kg·K |
| Coefficient of Thermal Expansion (αL) | 1.1×10-5 1/°C |
| Electrical Properties | Metric |
| Electrical Conductivity | 4.41×106 S/m |
| Electrical Resistivity | 2.27×10-7 Ω·m |
The values in this table are approximate and can vary depending on various factors such as the specific manufacturing process and heat treatment applied to the alloy.
Advantages & Disadvantages of 4820 Alloy Steel
| Advantages | Disadvantages |
|---|---|
| High strength | Limited corrosion resistance |
| Good wear resistance | Relatively low hardenability |
| Excellent toughness | Requires proper heat treatment |
| Good machinability | Not suitable for welding |
Applications of 4820 Alloy Steel
AISI 4820 steel, with its combination of high strength, good wear resistance, and toughness, finds applications in various industries. Some common applications of AISI 4820 steel include:
- Gears and Gear Shafts: AISI 4820 steel is frequently used in the manufacturing of gears, particularly in applications where high strength and wear resistance are essential.
- Axles and Shafts: Due to its excellent toughness and hardenability, AISI 4820 steel is often employed in the production of axles and shafts, especially in applications involving high stresses.
- Forging and Machining Components: The good machinability of AISI 4820 steel allows for ease of fabrication and shaping. It is commonly utilized in the manufacture of forged components like crankshafts, connecting rods, and other machinery parts.
- Bearings: AISI 4820 steel’s properties, including high strength, wear resistance, and hardenability, make it suitable for the production of anti-friction bearings and bearing components.
- Tooling and Die Manufacturing: The toughness and hardenability of AISI 4820 steel make it useful for tooling and die manufacturing, particularly in applications requiring high impact resistance and wear resistance.
- Automotive Components: AISI 4820 steel can be found in various automotive components, including drive shafts, differential gears, and transmission parts, due to its strength, toughness, and ability to withstand heavy loads and harsh operating conditions.