ASTM A897 Grade 3 (175-125-04) Austempered Ductile Iron Sheet,Plate

ASTM A897 Grade 3 (175-125-04) Austempered Ductile Iron Sheet/Plate Product Information -:- For detailed product information, please contact sales. -: ASTM A897 Grade 3 (175-125-04) Austempered Ductile Iron Sheet/Plate Synonyms -:- For detailed product information, please contact sales. -:

ASTM A897 Grade 3 (175-125-04) Austempered Ductile Iron Product Information -:- For detailed product information, please contact sales. -: ### **Product Technical Data Sheet: ASTM A897 Grade 3 Austempered Ductile Iron (Grade 175/125/04)** --- #### **1. Product Overview** **ASTM A897 Grade 3**, designated as **175/125/04**, represents the **highest strength category** of standardized Austempered Ductile Iron (ADI). This grade achieves exceptional mechanical properties through a precisely controlled isothermal heat treatment process that produces a unique **ausferritic microstructure** – a matrix of acicular ferrite and high-carbon stabilized austenite. With minimum tensile strength of **175 ksi (1207 MPa)**, yield strength of **125 ksi (862 MPa)**, and 4% elongation, Grade 3 ADI offers **performance comparable to heat-treated alloy steels** while maintaining the casting advantages, weight savings, and vibration damping characteristics of ductile iron. It is engineered for the most demanding structural applications where maximum strength-to-weight ratio and wear resistance are critical. --- #### **2. Governing Standards & Specifications** This premium ADI grade is defined by comprehensive international standards. * **Primary Standard: ASTM A897/A897M** - *Standard Specification for Austempered Ductile Iron Castings*. The grade is formally designated as **175/125/04**. * **International Equivalents:** * **ISO 17804:** *Austempered spheroidal graphite cast irons – Classification*. Corresponds to **JS/1200/4/380/12** (1200 MPa tensile, 4% elongation). * **SAE J2477** - *Austempered Ductile Iron (ADI)*. Recognizes equivalent high-strength grades. * **Key Testing Standards:** * **Tensile Test:** ASTM E8 / ISO 6892-1 * **Hardness:** ASTM E10 (Brinell) / ISO 6506 * **Impact Test:** ASTM E23 (Charpy) / ISO 148-1 * **Microstructure:** ASTM A247 / ISO 945 --- #### **3. Typical Chemical Composition (Base Iron for Austempering)** The base iron chemistry is meticulously controlled to ensure proper response to the austempering heat treatment. | Element | Target Range (%) | Critical Role for Grade 3 ADI | | :--- | :--- | :--- | | **Carbon (C)** | 3.5 - 3.8 | Provides carbon for austenite stabilization and ausferrite formation. Higher carbon enhances strength potential. | | **Silicon (Si)** | 2.4 - 2.8 | **Crucial element.** Suppresses carbide formation during austempering, promotes carbon enrichment of austenite, and controls transformation kinetics. | | **Manganese (Mn)** | ≤ 0.30 | Kept low to prevent segregation and formation of brittle phases at cell boundaries, which would reduce toughness. | | **Nickel (Ni)** | 0.8 - 1.5 | Enhances hardenability, promotes austenite stability, and improves toughness in heavy sections. | | **Molybdenum (Mo)** | 0.2 - 0.4 | **Essential for hardenability.** Ensures consistent transformation to ausferrite throughout the casting section, especially in thick parts. | | **Copper (Cu)** | 0.4 - 0.8 | Improves hardenability and promotes pearlite-free microstructure after austempering. | | **Magnesium (Mg)** | 0.03 - 0.05 | Ensures spheroidal graphite formation (nodularity >80%). | | **Trace Elements** | Tightly controlled | Elements that interfere with austempering (Sn, Sb, etc.) are minimized. | --- #### **4. Physical & Mechanical Properties** Grade 3 ADI delivers a unique combination of ultra-high strength with controlled ductility. | Property | Minimum Requirement / Typical Value | Test Standard & Notes | | :--- | :--- | :--- | | **Tensile Strength, min.** | **175 ksi (1207 MPa)** | ASTM A897 | | **Yield Strength (0.2% offset), min.** | **125 ksi (862 MPa)** | Exceptionally high yield-to-tensile ratio (~0.71). | | **Elongation, min.** | **4%** (in 2 inches / 50 mm) | Lower than lower-grade ADI but provides essential fracture resistance. | | **Hardness (Brinell)** | **388 - 444 HBW** | Typically 400-425 HBW. Provides exceptional wear and contact fatigue resistance. | | **Modulus of Elasticity** | 23.5 - 25.0 x 10⁶ psi (162 - 172 GPa) | Similar to other ductile irons. | | **Charpy Impact (V-notch) @ 23°C** | 8 - 15 J (Typical) | Adequate impact resistance for high-strength applications. | | **Fatigue Endurance Limit** | **500 - 600 MPa** (≈ 0.40-0.50 x UTS) | **Excellent fatigue performance**, often superior to quenched and tempered steels of equivalent hardness. | | **Density** | 0.256 lb/in³ (7.1 g/cm³) | ~10% lighter than steel. | | **Damping Capacity** | 3-5 times greater than steel | Significant advantage for vibration-prone applications. | | **Microstructure** | **Fine Ausferrite** (acicular ferrite + 20-30% high-carbon austenite) with spheroidal graphite. Achieved through austempering at **230-280°C (450-540°F)**. | The fine ausferritic structure provides the high strength and good fatigue resistance. | --- #### **5. Product Applications** Grade 3 ADI is specified for the most demanding components where traditional materials reach their limits. * **Heavy-Duty Automotive & Truck:** **High-performance crankshafts, connecting rods, gears, and differential carriers** for racing and heavy commercial vehicles. * **Mining & Construction Equipment:** **Gears, sprockets, track links, and roller wheels** for excavators, haul trucks, and bulldozers subjected to extreme wear and impact. * **Industrial Machinery:** **High-load gears, cams, rollers, and press components** requiring maximum wear resistance and fatigue strength. * **Railway:** **Brake discs, wheels, and coupler components** for high-speed and heavy-haul applications. * **Agriculture:** **Final drive gears and high-wear components** in combines and tractors. * **Defense:** **Armor components, track systems, and weapon system parts** where strength-to-weight ratio is critical. --- #### **6. Austempering Process & Fabrication Notes** * **Heat Treatment Process (Austempering):** 1. **Austenitize:** Heat to 1550-1700°F (845-925°C) 2. **Quench:** Rapidly cool to austempering temperature (450-540°F / 230-280°C) 3. **Hold:** Maintain at temperature for 1-4 hours to form ausferrite 4. **Cool:** Air cool to room temperature * **Machinability:** **Very difficult** in the austempered condition. Most machining should be performed prior to final heat treatment. **Carbide or ceramic tooling** is required for any post-austempering machining. * **Weldability:** **Not recommended.** The heat-affected zone loses the beneficial ausferritic structure and becomes brittle. If welding is unavoidable, specialized procedures with pre-heat and post-weld heat treatment are required. * **Grindability:** Good. Can be ground to precise dimensions with appropriate wheels. --- #### **7. Quality Assurance & Testing** * **Process Control:** Requires precise control of austempering temperature and time to achieve the target microstructure and properties. * **Testing Requirements:** Each production lot typically requires: * Tensile testing from separately cast test bars * Hardness testing * Microstructure verification (ausferrite content, nodularity) * Charpy impact testing may be specified for critical applications * **Non-Destructive Testing:** Magnetic particle or ultrasonic inspection is common for critical components. --- #### **8. Ordering Information** **Specify:** **"Austempered Ductile Iron Castings, ASTM A897 Grade 175/125/04 (Grade 3)."** **Essential Details to Include:** * **Part drawing and specifications** * **Required certifications** (material test reports with chemistry, mechanical properties, microstructure) * **Non-destructive testing requirements** * **Special processing requirements** (if any) **ASTM A897 Grade 3 ADI represents the pinnacle of ductile iron technology, offering designers a cast material solution that combines steel-like strength with the manufacturing and performance advantages of ductile iron for the world's most demanding applications.** -:- For detailed product information, please contact sales. -: ASTM A897 Grade 3 (175-125-04) Austempered Ductile Iron Specification Dimensions Size： Diameter 20-1000 mm Length <6564 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 A897 Grade 3 (175-125-04) Austempered Ductile Iron Properties -:- For detailed product information, please contact sales. -:

Applications of ASTM A897 Grade 3 (175-125-04) Austempered Ductile Iron Sheet,Plate -:- For detailed product information, please contact sales. -: Chemical Identifiers ASTM A897 Grade 3 (175-125-04) Austempered Ductile Iron Sheet,Plate -:- For detailed product information, please contact sales. -:

Packing of ASTM A897 Grade 3 (175-125-04) Austempered Ductile Iron Sheet/Plate -:- 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 Sheet/Plate 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 3035 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