Introduction
20Mn2 steel is a manganese steel that has excellent hardenability and strength. It is commonly used for components such as valves, pumps, crankshafts, transmissions and other parts that require a high level of strength. The alloy can be heat treated to generate a wide range of mechanical properties, making it an ideal choice for applications that demand toughness, strength, high temperature resistance, wear resistance and low fatigue.
Composition
20Mn2 steel is an alloy primarily composed of manganese, carbon, and silicon. The composition of the alloy, expressed in weight percent, is:
• Manganese (Mn): 20
• Carbon (C): 0.25–0.35
• Silicon (Si): 0.10–0.35
• Copper (Cu): 0.15–0.30
• Phosphorus (P): 0.035% max
• Sulfur (S): 0.030% max
Physical Properties
20Mn2 steel has a density of 7.85 g/cm3 and a melting point of 1530°C (2786°F). The alloy has a tensile strength of 620-870 MPa and an Elongation of 17-20% in a 50 mm gauge length. Its Poissons ratio is 0.27-0.30 and its Shear modulus is 78.5 GPa.
Applications
20Mn2 steel is commonly used in the manufacturing of parts for vehicles and machines, such as transmission gears, shafts, bearing housings, pistons, and other components that require high strength and toughness. Additionally, it is widely used for parts that require wear resistance and that continuously operate at elevated temperatures, such as valves, pumps, crankshafts, and cylinders, as well as for construction parts, agricultural equipment, and general engineering components. In order to obtain the desired properties, 20Mn2 steel should be heat treated under controlled temperatures.
Heat Treatment
20Mn2 steel can be heat treated to obtain a range of different mechanical properties. The following treatments are typically used:
• Annealing: Achieve ductility and better machinability.
• Normalizing: Increase hardness, strength and fatigue resistance.
• Tempering: Increase toughness, strength and wear resistance.
• Quenching: Increase hardness and strength.
Conclusion
20Mn2 steel is an excellent choice for components that require a high level of strength, toughness and wear resistance. The alloy has a good hardenability and it can be heat treated to obtain different mechanical properties, making it suitable for a wide variety of applications. It is commonly used for parts in vehicles and machines, as well as for agricultural applications and general engineering components.
