What are difference between LR EH36 and LR EH50 steel plate？

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

LR EH50 is an extra-high-strength marine steel plate also certified by Lloyd's Register (LR) with impact toughness tested at -40°C . The "50" denotes a minimum yield strength of 500 MPa . It has a higher tensile strength ranging from 610 to 770 MPa and minimum elongation of 18% for thicknesses up to 100mm . Impact energy requirements are minimum 50J (longitudinal) or 33J (transverse) at -40°C . The chemical composition features carbon ≤0.20%, manganese ≤1.70%, with microalloying elements including Nb, V, and Ti . This grade is designed for demanding structural components in shipbuilding, offshore platforms, and marine structures requiring superior strength-to-weight ratio.

Both LR EH36 and LR EH50 are LR-certified high-strength marine steels with excellent low-temperature toughness tested at -40°C, ensuring reliable performance in harsh marine environments including Arctic conditions . 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 EH50 provides a substantially higher minimum yield strength of 500 MPa with tensile strength reaching 610-770 MPa, designed for more demanding load-bearing applications requiring superior strength-to-weight ratio. Both grades feature controlled chemical composition and maintain good weldability for critical marine service.

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