Difference between DNV E500 and DNV E620 steel plate

DNV E500 and DNV E620 are high-strength structural steel plates certified by Det Norske Veritas (DNV) for demanding marine and offshore applications, such as ice-class vessels, offshore platforms, and advanced naval ships. The "E" designation guarantees excellent impact toughness at a low temperature of -40°C, making them suitable for operations in polar and harsh environments. The numerical suffix denotes the minimum yield strength in megapascals (MPa). Thus, DNV E500 provides a yield strength of at least 500 MPa, while DNV E620 offers a significantly higher minimum yield strength of 620 MPa.

Key Differences

The core distinction lies in their strength grade and the associated trade-offs in performance and application. DNV E620 provides approximately 24% higher yield strength than E500. This superior strength enables substantial weight reduction in critical structures or allows for designs that must withstand extreme loads, such as icebreaking hulls or heavy-lift vessel components. However, achieving this ultra-high strength in E620 requires more advanced alloying and precise thermomechanical processing. As a result, DNV E500 generally offers better overall weldability, formability, and fracture toughness compared to E620. The manufacturing and fabrication of E620 are more complex and costly. Therefore, the selection is dictated by specific engineering priorities: Choose DNV E620 where ultimate strength and weight savings are paramount for the most severe loading conditions; select DNV E500 for applications requiring an optimal balance of very high strength, reliable low-temperature toughness, and relatively easier fabrication.

Chemical Composition

Mechanical Property