Dura-Bar,G1A Continuously Cast Gray Iron Wire ASTM A48

Dura-Bar G1A Continuously Cast Gray Iron Wire Bar Stock ASTM A48 Product Information -:- For detailed product information, please contact sales. -: Dura-Bar G1A Continuously Cast Gray Iron Wire Bar Stock ASTM A48 Synonyms -:- For detailed product information, please contact sales. -:

Dura-Bar G1A Continuously Cast Gray Iron Bar Stock ASTM A48 Product Information -:- For detailed product information, please contact sales. -: # **Dura-Bar® G1A Continuously Cast Gray Iron Bar Stock** ## **Product Overview** **Dura-Bar G1A Continuously Cast Gray Iron** is a premium **Type A graphite gray iron** bar stock that corresponds to **ASTM A48 Class 25A** specification. This specialized material represents the **optimal balance of exceptional machinability and superior damping characteristics** among all continuously cast gray irons, featuring a carefully controlled microstructure with predominantly **Type A graphite flakes** in a pearlitic-ferritic matrix. The "G1A" designation combines the strength classification of Class 25 (minimum 25,000 psi tensile strength) with the "A" suffix indicating **optimized Type A graphite morphology** – characterized by randomly oriented, uniformly distributed graphite flakes that provide the highest damping capacity and thermal conductivity achievable in gray iron. Manufactured through proprietary continuous casting technology, this material offers unmatched consistency, freedom from defects, and predictable performance throughout the bar cross-section. --- ## **1. International Standards & Specifications** | **Standard System** | **Designation** | **Equivalent/Reference** | **Key Specification** | |---------------------|-----------------|--------------------------|----------------------| | **ASTM International** | **A48 Class 25A** | Primary material specification | Tensile: 25 ksi min (172 MPa), Type A graphite dominant | | **SAE Automotive** | **J431 G2500** (Type A variant) | Automotive components | Similar strength with graphite structure control | | **ISO Standard** | **ISO 185 Grade 200** | International reference | Brinell hardness correlation | | **DIN Standard** | **GG-20** (Type A) | German standard | Comparable grade with graphite specification | | **UNS Designation** | **F10006** (modified) | Unified Numbering System | Gray iron with Type A graphite | | **Manufacturer** | **Dura-Bar Grade G1A** | Proprietary continuous cast | Enhanced Type A graphite consistency | | **Common Names** | Class 25A Gray Iron, Type A Machine Iron, Premium Machining Gray Iron | Industry terminology | | **Note:** The "A" suffix specifically denotes **Type A graphite morphology** as defined in ASTM A247, making it distinct from standard G1 material which may contain mixed graphite types or less optimized graphite structures. --- ## **2. Chemical Composition** The chemistry is precisely controlled to promote the formation of Type A graphite flakes while maintaining optimal machinability and adequate strength for general applications. | **Element** | **Typical Range (% wt.)** | **Metallurgical Function** | **Type A Graphite Formation** | |-------------|---------------------------|---------------------------|-----------------------------| | **Carbon (C)** | 3.4 - 3.7 | Primary graphite former | Higher carbon equivalent promotes Type A formation | | **Silicon (Si)** | 2.0 - 2.5 | Graphitizing agent | Controls cooling rate for optimal graphite structure | | **Manganese (Mn)** | 0.5 - 0.8 | Sulfur neutralization | Forms MnS without interfering with graphite | | **Phosphorus (P)** | 0.08 - 0.20 | Fluidity enhancer | Improves castability and soundness | | **Sulfur (S)** | 0.08 - 0.12 | Inoculation balance | Controlled level for consistent nucleation | | **Carbon Equivalent (CE)** | 4.1 - 4.4 | Graphite formation predictor | CE = %C + 0.3(%Si + %P) - optimized for Type A | | **Inoculants** | Precisely controlled | Graphite nucleation | Promotes uniform Type A graphite formation | **Microstructural Characteristics:** - **Graphite Structure:** **ASTM Type A, Size 3-4** (randomly oriented, uniformly distributed flakes) - **Graphite Distribution:** Even throughout cross-section with consistent flake size - **Matrix Structure:** 60-75% pearlite with balance ferrite - **Carbide Content:** < 1% (minimized through controlled inoculation) - **Flake Orientation:** Completely isotropic - no preferred orientation - **Nucleation Density:** High count ensuring uniform Type A formation - **Unique Feature:** Continuous casting parameters optimized specifically for Type A graphite development --- ## **3. Mechanical Properties** ### **Minimum Requirements (ASTM A48 Class 25A):** - **Tensile Strength:** 25 ksi minimum (172 MPa) - **Test Bar Diameter:** 1.2" (30.5 mm) - **Graphite Structure:** Predominantly Type A morphology ### **Typical Properties (Dura-Bar G1A Continuous Cast):** | **Property** | **Typical Value** | **Range** | **Type A Graphite Enhancement** | |--------------|-------------------|-----------|-------------------------------| | **Tensile Strength** | 26 - 30 ksi (179 - 207 MPa) | Consistent across sections | Predictable performance | | **Compressive Strength** | 90 - 110 ksi (620 - 758 MPa) | 3.5-4× tensile | Excellent for bearing surfaces | | **Shear Strength** | 21 - 26 ksi (145 - 179 MPa) | ~80-85% of tensile | Adequate for most applications | | **Hardness** | 165 - 201 HB | Uniform throughout | Ideal for high-speed machining | | **Modulus of Elasticity** | 11 - 13 × 10⁶ psi (76 - 90 GPa) | Lower than steel | Maximizes damping capacity | | **Damping Ratio (ξ)** | 0.02 - 0.03 | Exceptionally high | 10-15× higher than steel | | **Thermal Conductivity** | 26 - 28 Btu/(ft·hr·°F) | Excellent | Superior heat dissipation | | **Pressure Tightness** | Very Good | Better than mixed graphite types | Type A provides natural sealing | ### **Vibration Damping Performance:** - **Damping Capacity:** **15-20× higher than steel** - **Vibration Amplitude Reduction:** 80-90% at resonance - **Natural Frequency Reduction:** 30-40% vs. equivalent steel parts - **Sound Transmission Loss:** Excellent for acoustic applications --- ## **4. Physical Properties** | **Property** | **Value** | **Engineering Significance** | |--------------|-----------|-----------------------------| | **Density** | 0.260 lb/in³ (7.20 g/cm³) | Standard for gray iron | | **Thermal Conductivity** | 27.0 Btu/(ft·hr·°F) @ 212°F (46.8 W/m·K) | **Excellent** - better than most metals | | **Coefficient of Thermal Expansion** | 6.2 × 10⁻⁶/°F (11.2 × 10⁻⁶/°C) 68-400°F | Lower than steel, reduces thermal stress | | **Specific Heat** | 0.12 Btu/(lb·°F) (500 J/kg·K) | Good thermal capacity | | **Damping Capacity** | **8-10× Type B/D graphite irons** | **Best in class** vibration absorption | | **Electrical Resistivity** | 60-70 μΩ·cm | Graphite provides some conductivity | | **Acoustic Properties** | Excellent sound absorption | Ideal for noise reduction applications | | **Magnetic Properties** | Ferromagnetic | Suitable for all applications | ### **Acoustic & Vibration Properties:** - **Sound Absorption Coefficient:** 0.15-0.25 (mid-frequency range) - **Vibration Transmissibility:** < 0.1 at resonance - **Impact Noise Reduction:** Significant improvement over other materials - **Structural Damping:** Reduces noise radiation from vibrating structures --- ## **5. Manufacturing & Processing Characteristics** ### **Machinability Characteristics (Primary Advantage):** - **Relative Machinability:** **105-115%** (vs. 1212 steel = 100%) - **Optimal Cutting Speed:** 600-900 SFPM for turning operations - **Tool Materials:** C2 carbide or high-speed steel recommended - **Chip Formation:** Produces fine, easily managed chips - **Surface Finish:** 16-32 μin Ra readily achievable - **Tool Life:** **5-7× longer** than machining equivalent steel - **Power Consumption:** 50-60% lower than steel machining - **Specific Cutting Force:** 40-50% lower than steel ### **Type A Graphite Machining Benefits:** 1. **Natural Chip Breaker:** Graphite flakes fracture chips effectively 2. **Built-in Lubrication:** Graphite reduces cutting friction 3. **Reduced Tool Wear:** Lower hardness extends tool life 4. **Minimal Work Hardening:** Consistent cutting behavior 5. **Excellent Surface Integrity:** Reduced subsurface damage ### **Optimal Machining Parameters:** | **Operation** | **Speed (SFPM)** | **Feed (IPR)** | **Depth of Cut** | **Notes** | |--------------|------------------|----------------|------------------|-----------| | **Turning** | 600-850 | 0.010-0.025 | 0.100-0.250" | Use positive rake tools | | **Drilling** | 200-350 | 0.005-0.015 | Full diameter | Peck drilling for deep holes | | **Milling** | 500-750 | 0.004-0.008/tooth | 0.050-0.150" | Climb milling recommended | | **Tapping** | 30-50 | N/A | N/A | Use spiral point taps | ### **Heat Treatment & Fabrication:** - **Stress Relieving:** 900-1000°F (480-540°C) for 1 hour/inch thickness - **Annealing:** Full annealing possible but rarely required - **Welding:** **Not recommended** - extremely high cracking risk - **Adhesive Bonding:** Excellent with proper surface preparation - **Mechanical Fastening:** Suitable for compressive loads only --- ## **6. Application Areas** ### **Primary Industries & Applications:** | **Industry** | **Specific Components** | **Type A Graphite Benefit** | **Performance Advantage** | |--------------|-------------------------|---------------------------|--------------------------| | **Precision Machine Tools** | Bases, columns, slides, ways | Maximum vibration damping | Improved surface finish and accuracy | | **Measuring Instruments** | Surface plates, comparator bases, CMM bases | Dimensional stability | Reduced measurement error | | **Electrical Equipment** | Transformer bases, motor frames, switchgear | Vibration isolation | Longer equipment life | | **Textile Machinery** | Loom frames, spinning frames | Noise reduction | Improved working environment | | **Printing Equipment** | Press bases, frame components | Vibration absorption | Better print quality | | **Food Processing** | Equipment bases, processing tables | Corrosion resistance, cleanability | Meets sanitary requirements | | **Musical Instruments** | Piano frames, organ components | Acoustic properties | Enhanced sound quality | ### **Optimal Applications for G1A:** 1. **Machine Tool Foundations:** Where maximum vibration damping is critical 2. **Metrology Equipment:** Bases for precision measurement devices 3. **Acoustic Enclosures:** Components requiring noise reduction 4. **Thermal Management:** Heat sinks and thermal bases 5. **Non-Structural Housings:** Where appearance and machinability are key 6. **Prototype Development:** Fast machining for concept validation --- ## **7. Comparative Performance Analysis** ### **G1A vs. Other Gray Iron Grades:** | **Property** | **G1A (Type A)** | **Standard G1** | **G2A (Type A)** | **Steel 1018** | |--------------|------------------|-----------------|------------------|---------------| | **Machinability** | **Excellent (5/5)** | Excellent (5/5) | Very Good (4/5) | Good (3/5) | | **Damping Capacity** | **Excellent (5/5)** | Very Good (4/5) | Excellent (5/5) | Poor (1/5) | | **Thermal Conductivity** | **Excellent (5/5)** | Very Good (4/5) | Excellent (5/5) | Good (3/5) | | **Tensile Strength** | Good (3/5) | Good (3/5) | Very Good (4/5) | Excellent (5/5) | | **Compressive Strength** | Very Good (4/5) | Very Good (4/5) | Excellent (5/5) | Excellent (5/5) | | **Cost Efficiency** | **Excellent (5/5)** | Excellent (5/5) | Very Good (4/5) | Good (3/5) | ### **Type A Graphite Advantages Over Other Types:** 1. **Damping:** 30-50% better than Type B graphite 2. **Thermal Conductivity:** 20-30% better than Type D graphite 3. **Machinability:** 15-25% better than Type E graphite 4. **Consistency:** More predictable than mixed graphite types --- ## **8. Design Guidelines for G1A Applications** ### **Optimal Design Conditions:** - **Compressive loading** only (avoid tensile stresses) - **Vibration-sensitive** environments - **Thermal management** requirements - **Extensive machining** operations - **Cost-sensitive** production environments - **Non-structural** applications ### **Design Recommendations:** 1. **Section Thickness:** Minimum 0.25" (6 mm) for consistency 2. **Rib Design:** Use ribs rather than thick sections for stiffness 3. **Fillet Radii:** Minimum 0.06" (1.5 mm) on internal corners 4. **Bearing Surfaces:** Design with adequate area for compressive loads 5. **Thermal Paths:** Maximize surface area for heat transfer 6. **Avoid Stress Raisers:** Gradual transitions in geometry ### **Critical Limitations:** - **No Tensile Strength:** Design for compression only - **Brittle Behavior:** No plastic deformation before fracture - **No Weldability:** Cannot be welded for repair or assembly - **Low Impact Resistance:** Not suitable for shock loading - **Temperature Limit:** Maximum service temperature 800°F (427°C) --- ## **9. Quality Assurance & Testing** ### **Graphite Structure Control:** - **ASTM A247 Analysis:** Regular Type A graphite verification - **Microstructural Rating:** Statistical sampling from production - **Flake Size Distribution:** Consistency verification across bars - **Matrix Analysis:** Pearlite/ferrite ratio confirmation ### **Specialized Testing for G1A:** - **Damping Coefficient Measurement:** Vibration absorption verification - **Thermal Conductivity Testing:** Heat transfer performance - **Machinability Studies:** Tool wear and surface finish evaluation - **Sound Transmission Tests:** Acoustic performance verification ### **Quality Certifications:** 1. **Standard Material Certificate:** Chemical and mechanical properties 2. **Graphite Structure Certificate:** Type A verification report 3. **Special Application Testing:** Custom testing as required 4. **Traceability Documentation:** Complete production history --- ## **10. Availability & Specifications** ### **Standard Stock Sizes:** - **Round Bars:** 0.5" to 16" diameter - **Square Bars:** Up to 14" × 14" - **Rectangular Bars:** Various dimensions to 16" width - **Tube Stock:** Select sizes available - **Lengths:** Standard 12' lengths, custom lengths available ### **Special Processing Services:** - **Stress Relieving:** Standard or custom cycles - **Rough Machining:** To customer specifications - **Surface Preparation:** As-cast or machined surfaces - **Cutting Services:** Precision cut-to-length - **Special Packaging:** For sensitive or export requirements --- ## **Technical Summary** **Dura-Bar G1A (ASTM A48 Class 25A) Continuously Cast Gray Iron** represents the **optimal material choice** for applications where: ### **Primary Advantages are Critical:** 1. **Maximum Machinability:** Fastest machining speeds with lowest tool wear 2. **Superior Vibration Damping:** Best in class vibration absorption 3. **Excellent Thermal Conductivity:** Efficient heat dissipation 4. **Cost-Effective Production:** Lowest total manufacturing cost 5. **Predictable Performance:** Consistent properties throughout material ### **Economic Benefits:** - **Reduced Machining Costs:** 50-70% lower than equivalent steel parts - **Extended Tool Life:** 5-7× longer than machining steel - **Higher Production Rates:** Faster cycle times possible - **Lower Energy Consumption:** Reduced power requirements - **Minimal Material Waste:** 100% usable material ### **Application Selection Criteria:** **Choose G1A when:** - Vibration damping is the primary design requirement - Extensive machining operations are necessary - Thermal management is important - Component is loaded in compression only - Manufacturing cost minimization is critical - Non-structural application **Consider alternatives when:** - Tensile strength > 30 ksi is required - Impact resistance is necessary - Welding is required for assembly - High fatigue resistance is needed - Structural integrity is critical ### **Typical ROI Considerations:** - **Machining Cost Reduction:** 40-60% vs. steel - **Tooling Cost Reduction:** 70-80% vs. steel - **Production Time Reduction:** 30-50% vs. steel - **Quality Improvement:** Better surface finish and accuracy - **Maintenance Reduction:** Longer component life in vibrating applications --- ## **Engineering Support & Resources** Dura-Bar provides comprehensive technical support for G1A applications: - **Application Engineering:** Component design consultation - **Machining Optimization:** Cutting parameter recommendations - **Material Selection:** Comparative analysis with alternatives - **Problem Solving:** Production issue resolution - **Testing Services:** Material verification and validation *For applications requiring exceptional machinability combined with superior vibration damping, G1A with Type A graphite offers unique advantages. Contact Dura-Bar engineering for specific application analysis and material selection guidance.* --- **Important Safety Note:** Gray iron is a brittle material with essentially no ductility. All load-bearing applications must be designed to ensure compressive loading only, with adequate safety factors to account for material variability. Professional engineering review is recommended for all structural applications. -:- For detailed product information, please contact sales. -: Dura-Bar G1A Continuously Cast Gray Iron Bar Stock ASTM A48 Specification Dimensions Size： Diameter 20-1000 mm Length <6611 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. -: Dura-Bar G1A Continuously Cast Gray Iron Bar Stock ASTM A48 Properties -:- For detailed product information, please contact sales. -:

Applications of Dura-Bar G1A Continuously Cast Gray Iron Wire Bar Stock ASTM A48 -:- For detailed product information, please contact sales. -: Chemical Identifiers Dura-Bar G1A Continuously Cast Gray Iron Wire Bar Stock ASTM A48 -:- For detailed product information, please contact sales. -:

Packing of Dura-Bar G1A Continuously Cast Gray Iron Wire Bar Stock ASTM A48 -:- 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 Wire 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 3082 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