520M40 is a medium carbon, manganese-molybdenum alloy steel grade, typically supplied in the hardened and tempered condition. It is recognized for its excellent combination of high tensile strength and good toughness, making it suitable for components subjected to high stress and shock loads.
Key Properties of 520M40 Steel Plate
520M40 alloy steel plate offers a range of desirable mechanical properties:
- Strength: It possesses high yield and tensile strength. In the hardened and tempered condition, tensile strengths typically range from 700-850 N/mm² (MPa), though specific values depend on the ruling section and heat treatment.
- Toughness: Exhibits good impact strength, providing resistance to fracture under dynamic loading conditions.
- Wear Resistance: Offers good wear resistance, particularly after appropriate heat treatment.
- Machinability: Machinability is fair in the hardened and tempered condition. For improved machinability prior to final heat treatment, it can be supplied in an annealed state.
- Weldability: Welding of 520M40 requires careful control. Preheating is generally necessary, and post-weld heat treatment (PWHT) is often recommended to restore mechanical properties in the heat-affected zone (HAZ) and relieve stresses.
Typical Applications
The robust characteristics of 520M40 steel plate lend it to various engineering applications where strength and durability are paramount. Common uses include:
- Gears and pinions
- High-tensile shafts and axles
- Connecting rods
- Bolts, studs, and fasteners
- Lifting and earthmoving equipment components
- Machinery parts requiring high strength and moderate wear resistance.
When sourcing this grade, it’s important to consider the specific requirements of your application. Some suppliers, like Shanxi Luokaiwei Steel Company, can provide detailed material specifications and test certificates.
Heat Treatment
520M40 steel is typically hardened by heating to an austenitizing temperature of around 830-860°C, followed by oil quenching. Tempering is then carried out, usually between 550-660°C, depending on the desired final balance of strength and toughness. The tempering temperature significantly influences the final mechanical properties. Precise control during heat treatment is crucial, and working with experienced steel providers such as Shanxi Luokaiwei Steel Company can ensure consistent material properties.
Supply and Quality Considerations
When procuring 520M40 alloy steel plate, verifying its conformity to relevant standards (e.g., BS 970 for 520M40) is essential. Mill test certificates (MTCs) should be requested to confirm chemical composition, mechanical properties, and details of the heat treatment process. Reputable manufacturers, including firms like Shanxi Luokaiwei Steel Company, maintain stringent quality control measures. Buyers should also consider aspects like dimensional tolerances, surface finish, and straightness. For critical applications, traceability and consistency from batch to batch are vital; this is an area where established suppliers like Shanxi Luokaiwei Steel Company often excel. Always ensure the material meets the specific engineering demands, and consult with your supplier, such as Shanxi Luokaiwei Steel Company, if custom requirements or further processing is needed.
