Difference between LR EH36 and LR EH69 steel plate

LR EH36 is a high-strength shipbuilding steel plate certified by Lloyd's Register (LR) . The "E" grade signifies it is impact tested at -40°C with minimum impact energy of 34J for longitudinal direction . It has a minimum yield strength of 355 MPa and tensile strength ranging from 490 to 620 MPa . The chemical composition is strictly controlled with carbon ≤0.18% and manganese 0.90-1.60% . Minimum elongation is 21% . This grade is widely used for hull construction, offshore platforms, and critical structural components of vessels operating in harsh marine conditions.

LR EH69 is an ultra-high-strength marine steel plate also certified by Lloyd's Register (LR) with impact toughness tested at -40°C . The "69" denotes a minimum yield strength of 690 MPa and tensile strength ranging from 770 to 940 MPa . Minimum elongation is 16% for thicknesses up to 100mm . The chemical composition features carbon ≤0.20%, manganese ≤1.70%, with microalloying elements including Nb, V, Ti, Cu, Cr, Ni, and Mo . This grade requires advanced processing like TMCP or quenching and tempering and is designed for the most critically stressed structural components in modern shipbuilding and offshore engineering, offering an exceptional strength-to-weight ratio.

Both LR EH36 and LR EH69 are LR-certified high-strength marine steels with excellent low-temperature toughness tested at -40°C, ensuring reliable performance in harsh marine environments. Their primary difference lies in strength level: EH36 offers a minimum yield strength of 355 MPa with tensile strength of 490-620 MPa, suitable for general high-strength hull construction, while EH69 provides a substantially higher minimum yield strength of 690 MPa with tensile strength reaching 770-940 MPa, designed for the most demanding load-bearing applications requiring maximum weight reduction. Both grades feature controlled chemical composition, but EH69 requires more advanced processing like TMCP or QT to achieve its superior mechanical properties while maintaining good weldability for critical marine service.

Chemical Composition

Mechanical Property