Difference between BV D460 and BV D690 steel plate

BV D460 is a high-strength shipbuilding steel plate certified by Bureau Veritas (BV) . The "D" grade signifies it is impact tested at -20°C . It has a minimum yield strength of 460 MPa and tensile strength ranging from 570 to 720 MPa . Minimum elongation is 17% . Impact energy requirements are 31J (transverse) or 46J (longitudinal) at -20°C . The chemical composition is strictly controlled with carbon ≤0.20% and manganese ≤1.70% . This grade is typically supplied in quenched and tempered (QT) or thermomechanical controlled processed (TMCP) conditions . It is widely used for hull construction, decks, and structural components of ships and offshore structures.

BV D690 is an ultra-high-strength marine steel also certified by Bureau Veritas (BV) with impact toughness tested at -20°C . The "690" denotes a minimum yield strength of 690 MPa . It has a tensile strength ranging from 770 to 940 MPa and minimum elongation of 14% . Impact energy requirements are 46J (transverse) or 69J (longitudinal) at -20°C . The chemical composition includes carbon ≤0.20%, manganese ≤1.70%, and microalloying elements . This grade requires advanced processing and is exclusively supplied in quenched and tempered (QT) or TMCP conditions . It is designed for the most demanding structural components in shipbuilding, ultra-deepwater offshore platforms, and marine structures requiring maximum strength-to-weight ratio.

Both BV D460 and BV D690 are BV-certified high-strength marine steels with impact toughness tested at -20°C, ensuring reliable performance in cold marine environments . Their primary difference lies in strength level: D460 offers a minimum yield strength of 460 MPa with tensile strength of 570-720 MPa, suitable for general high-strength hull construction , while D690 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 strength-to-weight ratio . Both grades feature controlled chemical composition with carbon ≤0.20% and manganese ≤1.70% , and require advanced processing like QT or TMCP to achieve their superior mechanical properties while maintaining good weldability for critical marine service.

Chemical Composition

Mechanical Property