ABS DQ47 is an extra-high-strength marine steel plate certified by the American Bureau of Shipping (ABS) , produced through quenching and tempering (Q&T) . The "DQ" designation 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, with minimum elongation of 17% . Impact energy requirements are minimum 46J (longitudinal) or 31J (transverse) at -20°C . This grade offers excellent toughness and corrosion resistance, and is widely used in offshore drilling platforms, FPSOs, and shipbuilding.
ABS DQ63 is an ultra-high-strength marine steel plate also certified by ABS, produced through quenching and tempering (Q&T) . The "63" denotes a minimum yield strength of 620 MPa and tensile strength ranging from 720 to 890 MPa, with minimum elongation of 15% . Impact testing is performed at -20°C, with minimum energy requirements of 62J (longitudinal) or 41J (transverse) . The chemical composition includes carbon ≤0.20% and manganese ≤1.70% . This grade is designed for critical offshore structures, including drilling platforms and marine engineering projects.
Both ABS DQ47 and ABS DQ63 are ABS-certified, quenched and tempered ultra-high-strength marine steels with excellent toughness tested at -20°C, ensuring reliable performance in harsh marine environments . Their primary difference lies in strength level: DQ47 offers a minimum yield strength of 460 MPa with tensile strength of 570-720 MPa, suitable for high-strength offshore platforms and shipbuilding , while DQ63 provides a substantially higher minimum yield strength of 620 MPa with tensile strength reaching 720-890 MPa, designed for the most demanding load-bearing applications requiring maximum strength-to-weight ratio . Both grades maintain good weldability and are essential for critical marine structural applications.
Chemical Composition
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ABS DQ47 Extra high Strength Chemical Composition in Tempering and Quenching |
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Grade |
The Element Max (%) |
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|
C |
Si |
Mn |
P |
S |
N |
|
|
ABS DQ47 |
0.20 |
0.55 |
1.7 |
0.035 |
0.035 |
0.02 |
|
ABS DQ63 Extra high Strength Chemical Composition in Tempering and Quenching |
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|
Grade |
The Element Max (%) |
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|
C |
Si |
Mn |
P |
S |
N |
|
|
ABS DQ63 |
0.20 |
0.55 |
1.7 |
0.030 |
0.030 |
0.02 |
Mechanical Property
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ABS DQ47 Extra high strength property in tempering and quenching |
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|
Grade |
Mechanical Property |
Charpy V Impact Test |
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|
Yield |
Tensile |
Elongation |
Degree |
Energy 1 |
Energy 2 |
|
|
Min Mpa |
Mpa |
Min % |
-20 |
J |
J |
|
|
ABS DQ47 |
460 |
570-720 |
17 |
31 |
46 |
|
|
Note: Energy 1 is transverse impact test, Energy 2 is longitudinal |
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|
ABS DQ63Extra high strength property in tempering and quenching |
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|
Grade |
Mechanical Property |
Charpy V Impact Test |
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|
Yield |
Tensile |
Elongation |
Degree |
Energy 1 |
Energy 2 |
|
|
Min Mpa |
Mpa |
Min % |
-20 |
J |
J |
|
|
ABS DQ63 |
620 |
720-890 |
15 |
41 |
62 |
|
|
Note: Energy 1 is transverse impact test, Energy 2 is longitudinal |
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