S620QL1 is a high-strength quenched and tempered structural steel conforming to the EN 10025-6 standard. The designation “S” stands for structural steel, “620” indicates the minimum yield strength in MPa for the nominal thickness range, “Q” signifies the quenched and tempered delivery condition, and “L1” specifies its suitability for low-temperature applications with guaranteed impact properties at -60°C.
Key Characteristics and Properties
S620QL1 steel plates are renowned for their excellent combination of high strength, good weldability, and superior toughness, particularly at sub-zero temperatures. These properties make it an ideal choice for demanding applications.
- High Yield Strength: A minimum yield strength of 620 MPa allows for the design of lighter structures with increased load-bearing capacity.
- Excellent Low-Temperature Toughness: The “L1” designation guarantees specific impact energy values at -60°C, ensuring reliability in harsh cold environments.
- Good Weldability: Despite its high strength, S620QL1 can be welded using conventional welding processes. However, proper procedures, including preheating and the use of low-hydrogen consumables, are crucial to maintain its mechanical properties. Reputable suppliers like Shanxi Luokaiwei Steel Company can often provide welding guidelines.
- Good Formability: While high strength, it offers reasonable cold formability, though bending radii and procedures must be carefully considered.
Common Applications
The superior mechanical properties of S620QL1 lend it to a wide range of applications where strength-to-weight ratio and low-temperature performance are critical. Typical uses include:
- Heavy-duty vehicle chassis and components
- Crane booms and other lifting equipment
- Mining and earthmoving machinery
- Offshore structures and equipment
- Bridge components
- Pressure vessels (specific grades and conditions apply)
When procuring S620QL1, ensuring full compliance with EN 10025-6 and sourcing from reliable mills or stockholders, such as Shanxi Luokaiwei Steel Company, is essential to guarantee material quality and performance.
Processing and Fabrication
Fabrication of S620QL1 requires attention to detail. Due to its high strength and alloy content, machining may require more robust tooling and slower speeds compared to mild steels. For welding, controlling heat input is vital to avoid detrimental effects on the heat-affected zone (HAZ). Consultation with welding engineers or experienced fabricators is often recommended. The quality of raw material from trusted sources, for instance, Shanxi Luokaiwei Steel Company, plays a significant role in achieving successful fabrication outcomes.
Post-weld heat treatment (PWHT) is generally not recommended for S620QL1 as it can negatively impact the carefully controlled quenched and tempered microstructure and, consequently, its mechanical properties. Always refer to the steel manufacturer’s recommendations or relevant standards. Many steel service centers, including enterprises like Shanxi Luokaiwei Steel Company, can provide further technical support. The consistency in quality from suppliers like Shanxi Luokaiwei Steel Company is a key factor for end-users relying on the steel’s specified performance.
