ASTM A131 Steel, grade DH32

ASTM A131 Steel, grade DH32 Product Information -:- For detailed product information, please contact sales. -: ASTM A131 Steel, grade DH32 Synonyms -:- For detailed product information, please contact sales. -:

ASTM A131 Steel, grade DH32 Product Information -:- For detailed product information, please contact sales. -: ### **Technical Data Sheet: ASTM A131/A131M Structural Steel for Ships, Grade DH32** --- #### **1. Product Overview** ASTM A131 Grade DH32 is a **high-strength, low-temperature service** steel plate specifically designed for shipbuilding applications requiring enhanced mechanical properties and improved toughness. The "D" indicates its impact testing temperature category, while "H32" signifies high strength with a specified minimum yield strength of 315 MPa (32 kgf/mm²). This grade is produced with fine grain practice and is suitable for critical structural components in large vessels and offshore structures. --- #### **2. International Standards & Equivalents** | Standard Organization | Designation | |-----------------------|-------------| | **ASTM International** | **A131/A131M Grade DH32** | | **ABS (American Bureau of Shipping)** | **Grade DH32** | | **Lloyd's Register** | **Grade DH32** | | **DNV** | **Grade DH32** | | **European Norm (EN)** | **EH32** (EN 10025) | | **Chinese GB** | **DH32** (GB 712) | | **Japanese (JIS)** | **KA32** | --- #### **3. Chemical Composition (Weight %)** | Element | Composition (%) | |---------|-----------------| | **Carbon (C)** | 0.18 max | | **Manganese (Mn)** | 0.90-1.60 | | **Phosphorus (P)** | 0.025 max | | **Sulfur (S)** | 0.025 max | | **Silicon (Si)** | 0.10-0.50 | | **Aluminum (Al)** | 0.015 min (for fine grain practice) | | **Niobium (Nb)** | 0.02-0.05 | | **Vanadium (V)** | 0.05-0.10 | | **Titanium (Ti)** | 0.02 max | | **Copper (Cu)** | 0.35 max | | **Iron (Fe)** | Balance | **Key Composition Features:** - **Microalloying Elements**: Nb, V, or Ti additions for grain refinement and precipitation strengthening - **Carbon Equivalent (Ceq)**: Typically ≤ 0.40% for good weldability - **Fine Grain Practice**: Achieved through Al treatment and controlled rolling - **Enhanced Manganese Content**: Provides solid solution strengthening --- #### **4. Mechanical Properties** **Tensile Properties:** - **Tensile Strength**: 470-590 MPa (68-86 ksi) - **Yield Strength**: 315 MPa (46 ksi) min - **Elongation in 50 mm (2 in)**: 22% min - **Yield to Tensile Ratio**: 0.67-0.80 typical **Impact Properties:** - **Charpy V-Notch Test Temperature**: **-20°C (-4°F)** - **Minimum Impact Energy**: **34 J (25 ft-lbf)** - **Test Direction**: Longitudinal and transverse as specified --- #### **5. Physical Properties** | Property | Value | |----------|-------| | **Density** | 7.85 g/cm³ (0.284 lb/in³) | | **Modulus of Elasticity** | 200 GPa (29,000 ksi) | | **Poisson's Ratio** | 0.29 | | **Thermal Conductivity** | 48.0 W/m·K at 20°C | | **Coefficient of Thermal Expansion** | 12.0 × 10⁻⁶ /K (20-100°C) | | **Specific Heat Capacity** | 450 J/kg·K | --- #### **6. Product Applications** **Primary Marine Applications:** - Large container ship hull structures - Bulk carrier side shells and decks - Oil tanker bottom plating and longitudinal - Offshore platform module support structures - LNG carrier secondary barrier systems **Specific Component Usage:** - Main deck plating in way of openings - Bottom plating in slamming areas - Longitudinal bulkheads in cargo holds - Transverse frames and web frames - Hatch coamings and strengthening members --- #### **7. Fabrication Characteristics** **Welding Performance:** - Good weldability with proper procedures - Recommended processes: FCAW, SAW, GMAW - **Pre-heat Requirements**: 50-125°C depending on thickness - **Carbon Equivalent (Ceq)**: 0.36-0.40% typical - **Filler Metal Selection**: AWS E81T1-K2, E91T1-K3 or equivalent **Forming Operations:** - Good cold forming characteristics - Suitable for bending and rolling operations - Minimum bending radii per classification society rules - Excellent flame cutting performance **Heat Treatment:** - Typically supplied in as-rolled or controlled rolled condition - Normalizing available when specified - TMCP (Thermo-Mechanical Controlled Process) commonly used --- #### **8. Quality Assurance & Testing** **Mandatory Tests:** - Chemical analysis (ladle and product analysis) - Tension test from each plate - **Charpy V-notch impact test at -20°C** - Bend test when specified - Fine austenitic grain size verification **Additional Tests:** - Ultrasonic examination per ASTM A578 - Through-thickness testing (Z-quality) when specified - Hardness testing for welding procedure qualification --- #### **9. Corrosion Performance** - **Marine Atmosphere**: Good resistance with proper coating systems - **Seawater Corrosion**: Requires cathodic protection - **Corrosion Rate**: ~0.1-0.2 mm/year in splash zone - **Recommended Protection**: Epoxy coatings + sacrificial anodes --- #### **10. Available Product Forms** - Plates: 6 mm to 150 mm thickness - Standard widths: 1500-4500 mm - Standard lengths: 6000-18000 mm - Special dimensions available per mill capability --- **Technical Notes:** - Grade DH32 provides 34% higher yield strength than conventional Grade A steel - Suitable for service temperatures down to -20°C (-4°F) - Requires certified welding procedures matching the strength level - TMCP processing provides excellent combination of strength and toughness - Must comply with classification society rules for high-strength steel applications *This information is for reference purposes. For complete requirements and current specifications, consult the latest ASTM A131/A131M standard and applicable classification society rules. Always verify mechanical properties with current certified mill test reports before fabrication.* -:- For detailed product information, please contact sales. -: ASTM A131 Steel, grade DH32 Specification Dimensions Size： Diameter 20-1000 mm Length <4224 mm Size:We can customized as required Standard： Per your request or drawing We can customized as required Properties（Theoretical） Chemical Composition -:- For detailed product information, please contact sales. -: ASTM A131 Steel, grade DH32 Properties -:- For detailed product information, please contact sales. -:

Applications of ASTM A131 Steel, grade DH32 -:- For detailed product information, please contact sales. -: Chemical Identifiers ASTM A131 Steel, grade DH32 -:- For detailed product information, please contact sales. -:

Packing of ASTM A131 Steel, grade DH32 -:- For detailed product information, please contact sales. -: Standard Packing: -:- For detailed product information, please contact sales. -: Typical bulk packaging includes palletized plastic 5 gallon/25 kg. pails, fiber and steel drums to 1 ton super sacks in full container (FCL) or truck load (T/L) quantities. Research and sample quantities and hygroscopic, oxidizing or other air sensitive materials may be packaged under argon or vacuum. Solutions are packaged in polypropylene, plastic or glass jars up to palletized 695 gallon liquid totes Special package is available on request. E FORUs’ is carefully handled to minimize damage during storage and transportation and to preserve the quality of our products in their original condition