ASTM A203 Low Alloy Steel Rod/Bar, Grade D

ASTM A203 Low Alloy Steel Rod, Grade D Product Information -:- For detailed product information, please contact sales. -: ASTM A203 Low Alloy Steel Rod, Grade D Synonyms -:- For detailed product information, please contact sales. -:

ASTM A203 Low Alloy Steel, Grade D Product Information -:- For detailed product information, please contact sales. -: ### **Product Introduction: ASTM A203 Grade D Steel** **ASTM A203 Grade D** is a nickel-alloy steel plate designed for pressure vessel applications requiring excellent low-temperature toughness. With a nominal **3.50% nickel** content, this grade offers superior impact resistance at cryogenic temperatures, making it suitable for severe low-temperature service conditions where enhanced fracture toughness is critical. --- #### **1. International Standards & Grades** **Primary Standard:** **ASTM A203/A203M** - "Standard Specification for Pressure Vessel Plates, Alloy Steel, Nickel" **Grade Classification:** - **Grade D** - 3.50% nickel steel for severe low-temperature service - Other grades: A, B, E, F with varying nickel content **International Equivalents:** - **EN 10028-4**: 12Ni19 - **JIS G3127**: SLA 235B - **GB/T 3531**: 09MnNiDR - **ISO 9328-4**: 12Ni19 --- #### **2. Chemical Composition** The chemical composition requirements for ASTM A203 Grade D: | Element | Composition (Maximum %) | |---|---| | Carbon (C) | 0.17 | | Manganese (Mn) | 0.70 | | Phosphorus (P) | 0.035 | | Sulfur (S) | 0.040 | | Silicon (Si) | 0.30 | | Nickel (Ni) | 3.25-3.75 | **Key Composition Features:** - **Enhanced Nickel Content**: 3.25-3.75% for superior low-temperature toughness - **Low Carbon**: Ensures excellent weldability and fracture resistance - **Controlled Manganese**: Maintains optimal strength-toughness balance - **Restricted Silicon**: Maximizes impact properties --- #### **3. Physical & Mechanical Properties** **Mechanical Properties (for thicknesses ≤ 50 mm):** | Property | Value | |---|---| | **Tensile Strength** | 515-655 MPa (75-95 ksi) | | **Yield Strength (min.)** | 310 MPa (45 ksi) | | **Elongation in 2" (min.)** | 21% | | **Elongation in 8" (min.)** | 24% | **Low-Temperature Toughness Properties:** - **Charpy V-Notch Test Temperature**: -150°F (-101°C) - **Minimum Impact Energy**: 20 ft-lbf (27 J) - **Exceptional Toughness**: Maintains properties at extreme cryogenic temperatures **Physical Properties:** - **Density**: 7.87 g/cm³ (0.284 lb/in³) - **Modulus of Elasticity**: 201 GPa (29,150 ksi) - **Thermal Conductivity**: 48.5 W/m·K - **Coefficient of Thermal Expansion**: 11.4 × 10⁻⁶/°C - **Specific Heat Capacity**: 475 J/kg·K --- #### **4. Product Applications** **Severe Cryogenic Service:** - Liquid ethylene storage tanks - LNG processing equipment - Cryogenic research vessels - Ultra-low temperature storage systems **Chemical Processing:** - Ethylene cracker components - Low-temperature reactor vessels - Cryogenic distillation columns - Specialized chemical process equipment **Energy and Power:** - LNG liquefaction plant equipment - Cryogenic power generation systems - Advanced energy storage vessels - Specialized heat exchangers **Industrial Applications:** - Industrial gas liquefaction equipment - Cryogenic testing facilities - Specialized research equipment - Advanced cooling systems --- #### **5. Fabrication Characteristics** **Welding Performance:** - **Good Weldability**: Requires nickel-matched filler metals - **Preheat Requirements**: 200-250°F (95-120°C) recommended - **Post-Weld Heat Treatment**: Stress relieving at 1100-1150°F (595-620°C) - **Recommended Processes**: GTAW, GMAW, SMAW (low-hydrogen) - **Filler Metals**: ENiCrFe-2, ENiCrFe-3 or equivalent **Forming & Machining:** - **Excellent Formability**: Suitable for complex forming operations - **Machinability**: Good (approximately 65% of B1112 steel) - **Cutting Methods**: Waterjet, laser, and plasma cutting preferred - **Bend Performance**: Superior at low temperatures **Heat Treatment:** - Supplied in normalized and tempered condition - Normalizing temperature: 1550-1650°F (845-900°C) - Tempering temperature: 1100-1200°F (595-650°C) - Microstructural stability ensured **Quality Assurance:** - **Mandatory Impact Testing**: Charpy V-Notch at -150°F (-101°C) - **Chemical Analysis**: Complete heat certification - **Mechanical Testing**: Comprehensive property verification - **Non-Destructive Testing**: UT, RT, PT as specified --- ### **Technical Summary** ASTM A203 Grade D represents a premium nickel-alloy steel engineered for the most demanding cryogenic applications. The 3.50% nickel content provides exceptional toughness at temperatures as low as -150°F (-101°C), making this grade suitable for handling liquefied gases and operating in extreme low-temperature environments. The enhanced nickel content significantly improves the material's fracture toughness and lowers the ductile-to-brittle transition temperature, providing an additional safety margin for critical cryogenic applications. The 45 ksi minimum yield strength offers excellent structural efficiency while maintaining the required toughness properties. This grade demonstrates superior performance in fabricated cryogenic equipment, with welding characteristics that allow for the construction of complex pressure vessels and storage systems. The material's consistent response to thermal processing and reliable mechanical properties make it a preferred choice for engineers designing equipment for the LNG industry, ethylene production, and advanced cryogenic applications. ASTM A203 Grade D has established itself as a reliable solution for severe cryogenic service, offering performance characteristics that bridge the gap between lower nickel grades and more expensive high-nickel alloys. Its proven service history in critical low-temperature applications ensures continued preference among engineers and fabricators working with extreme cryogenic conditions. -:- For detailed product information, please contact sales. -: ASTM A203 Low Alloy Steel, Grade D Specification Dimensions Size： Diameter 20-1000 mm Length <4333 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 A203 Low Alloy Steel, Grade D Properties -:- For detailed product information, please contact sales. -:

Applications of ASTM A203 Low Alloy Steel Rod, Grade D -:- For detailed product information, please contact sales. -: Chemical Identifiers ASTM A203 Low Alloy Steel Rod, Grade D -:- For detailed product information, please contact sales. -:

Packing of ASTM A203 Low Alloy Steel Rod, Grade D -:- 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 Rod 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 804 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