SAE/AISI 4720 Alloy Steel (UNS G47200)
SAE/AISI 4720 is a nickel-chromium-molybdenum alloy steel that is commonly used in automotive applications due to its excellent mechanical properties, including high strength, toughness, and wear resistance.
| Chemical Composition | ||
|---|---|---|
| Element | Min | Max |
| Iron | 96.705% | 97.78% |
| Carbon | 0.17% | 0.22% |
| Chromium | 0.35% | 0.55% |
| Manganese | 0.50% | 0.70% |
| Molybdenum | 0.15% | 0.25% |
| Nickel | 0.90% | 1.20% |
| Phosphorous | 0.035% | |
| Silicon | 0.15% | 0.30% |
| Sulfur | 0.04% | |
The following table provides a list of SAE/AISI 4720 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 |
| 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 | 187 - 229 |
| Thermal Properties | Metric |
| Thermal Conductivity | 44.5 W/m·K |
| Specific Heat Capacity (Cp) | 470 J/kg·K |
| Coefficient of Thermal Expansion (αL) | 1.3×10-5 1/°C |
| Electrical Properties | Metric |
| Electrical Conductivity | 4.23×106 S/m |
| Electrical Resistivity | 2.36×10-7 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 4720 Alloy Steel
| Advantages | Disadvantages |
|---|---|
| High strength | High cost |
| Good wear resistance | Low machinability |
| Good toughness | Difficult to weld |
Applications of 4720 Alloy Steel
AISI 4720 steel is commonly used in applications where a combination of strength and toughness is required. Some common applications of 4720 steel include:
- Forgings: 4720 steel is a popular choice for forgings because it can be heat treated to achieve a wide range of properties. It is commonly used in the production of gears, shafts, axles, crankshafts, connecting rods, pistons, bearings, and other parts that require strength, wear resistance, and toughness.
- Machined parts: 4720 steel can also be machined to a high degree of accuracy and precision. It is commonly used in the production of gears, shafts, axles, and other parts that require strength, wear resistance, and toughness.
- Castings: 4720 steel can be cast into a variety of shapes and sizes. It is commonly used in the production of gears, shafts, axles, crankshafts, connecting rods, pistons, bearings, and other parts that require strength, wear resistance, and toughness.
- Welding: 4720 steel can be welded, but it is important to use a qualified welder and the proper welding techniques.
- Heat treatment: 4720 steel can be heat treated to achieve a wide range of properties. It is commonly used in the production of gears, shafts, axles, crankshafts, connecting rods, pistons, bearings, and other parts that require strength, wear resistance, and toughness.