Introduction
LR DH42 is grade of high-strength structural steel plates specifically designed for use in the marine industry. The grade offer excellent mechanical properties, corrosion resistance, and weldability, making them ideal for constructing ships, offshore platforms, and other marine structures.
Chemical Composition
The chemical composition of LR DH42 steel plates is carefully controlled to ensure their desired mechanical properties. These plates typically contain carbon (C), manganese (Mn), phosphorus (P), sulfur (S), silicon (Si), and other alloying elements such as chromium (Cr), nickel (Ni), copper (Cu), and molybdenum (Mo) in specific ranges.
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LR DH42 extra high Strength Chemical Composition |
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Grade |
The Element Max (%) |
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C |
Si |
Mn |
P |
S |
Al |
N |
|
|
LR DH42 |
0.20 |
0.55 |
1.70 |
0.030 |
0.030 |
0.015 |
0.020 |
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Nb |
V |
Ti |
Cu |
Cr |
Ni |
Mo |
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|
0.02-0.05 |
0.03-0.10 |
0.02 |
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Mechanical Properties
The mechanical properties of LR DH42 steel plates are outstanding, with high yield strength, tensile strength, and elongation values. These plates also exhibit good impact toughness and are suitable for use in low-temperature environments.
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LR DH42 extra high strength property |
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Grade |
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Mechanical Property |
Charpy V Impact Test |
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Thickness |
Yield |
Tensile |
Elongation |
Degree |
Energy 1 |
Energy 2 |
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|
LR DH42 |
mm |
Min Mpa |
Mpa |
Min % |
-20 |
J |
J |
|
t≤50 |
420 |
530-680 |
20% |
28 |
42 |
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50＜t≤70 |
420 |
530-680 |
20% |
28 |
42 |
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70＜t≤100 |
420 |
530-680 |
20% |
28 |
42 |
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Note: Energy 1 is transverse impact test, Energy 2 is longitudinal |
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Heat Treatment
To achieve the desired mechanical properties, LR DH42 steel plates undergo controlled heat treatment processes, such as normalizing or quenching and tempering. These processes help to optimize the microstructure of the steel, ensuring consistent and reliable performance in marine applications.
Impact Testing
Impact testing is a crucial aspect of ensuring the structural integrity of marine steel plates. LR DH42 plates are subjected to rigorous impact testing at various temperatures to assess their ability to withstand sudden loads and impacts without failing.
