Difference between LR EH32 and LR EH50 steel plate

LR EH32 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 315 MPa (46 ksi) and tensile strength ranging from 440 to 590 MPa (64-85 ksi), with minimum elongation of 22% . The chemical composition is strictly controlled with carbon ≤0.18% and manganese 0.90-1.60% . Impact energy requirements at -40°C are minimum 31J (longitudinal) for thicknesses up to 50mm. This grade is widely used for hull construction, offshore platforms, and marine structures .

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% . The chemical composition features carbon ≤0.20%, manganese ≤1.70%, with microalloying elements including Nb, V, and Ti . Impact energy requirements at -40°C are minimum 50J (longitudinal) for thicknesses up to 50mm . This grade is designed for demanding structural components in shipbuilding and offshore platforms requiring superior strength-to-weight ratio .

Both LR EH32 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: EH32 offers a minimum yield strength of 315 MPa with tensile strength of 440-590 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. Both grades feature controlled chemical composition and require advanced processing like TMCP or normalized rolling to achieve their mechanical properties while maintaining good weldability for critical marine service.

Chemical Composition

Mechanical Property