Difference between LR AH32 and LR AH46 steel plate

LR AH32 is a higher-strength structural steel plate certified by Lloyd's Register (LR) for shipbuilding and marine applications. The "A" grade signifies it is impact tested at 0°C (32°F), ensuring adequate toughness for general marine environments . It has a minimum yield strength of 315 MPa (46 ksi) and tensile strength ranging from 440 to 590 MPa (64-83 ksi), with a minimum elongation of 22% . Its chemical composition is strictly controlled with carbon ≤0.18% and manganese 0.90-1.60% . This grade is widely used for hull structures and general shipbuilding components.

LR AH46 is an extra-high-strength marine steel plate also certified by Lloyd's Register (LR) , with impact toughness tested at 0°C . The "46" denotes a minimum yield strength of 460 MPa and tensile strength ranging from 570 to 720 MPa, with a minimum elongation of 19% . The chemical composition is strictly controlled with carbon ≤0.21% and manganese ≤1.70%, and may include microalloying elements such as Nb and V . This grade is typically supplied in normalized or TMCP conditions and is designed for more demanding structural applications requiring superior strength.

Both LR AH32 and LR AH46 are LR-certified high-strength marine steels with impact toughness tested at 0°C, ensuring reliable performance in general marine environments. Their primary difference lies in strength level: AH32 offers a minimum yield strength of 315 MPa with tensile strength of 440-590 MPa, suitable for general high-strength hull construction , while AH46 provides a substantially higher minimum yield strength of 460 MPa with tensile strength reaching 570-720 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 . The selection between them depends on whether the project requires the balanced strength of AH32 or the enhanced performance of AH46 for more extreme structural demands.

Chemical Composition

Mechanical Property