Spherical ASTM A699 Steel Powder, class 2

ASTM A699 Steel Spherical Powder, class 2 Product Information -:- For detailed product information, please contact sales. -: ASTM A699 Steel Spherical Powder, class 2 Synonyms -:- For detailed product information, please contact sales. -: -:- For detailed product information, please contact sales. -: Spherical ASTM A699 Steel Powder, class 2 characteristics -:- For detailed product information, please contact sales. -: Spherical ASTM A699 Steel Powder, class 2 Particle Size -:- For detailed product information, please contact sales. -: -:- -:- 0-15μm ,5-25μm, 15-45μm, 15-53μm,20-63um, 45-75μm, 45-105μm, 45-150μm ,75-150μm. (Various granularities can be customized according to customer requirements) -:- For detailed product information, please contact sales. -:

Spherical ASTM A699 Steel Powder, class 2 Applicable processes -:- For detailed product information, please contact sales. -: Laser/electron beam additive manufacturing (SLM/EBM, 3D printing) Direct laser deposition (DLD) Used in thermal spray (TSA) Powder hot isostatic pressing (HIP) Metal injection molding (MIM) Powder metallurgy (PM) Laser cladding (LC), etc. -:- For detailed product information, please contact sales. -: Spherical ASTM A699 Steel Powder, class 2 Chemical Composition -:- For detailed product information, please contact sales. -: -:- For detailed product information, please contact sales. -: ASTM A699 Steel, class 2 Product Information -:- For detailed product information, please contact sales. -: # Technical Data Sheet: ASTM A699 Steel, Class 2 **Cold-Worked, High-Carbon, High-Strength Spring Steel** --- ## 1. PRODUCT OVERVIEW **Standard Designation:** ASTM A699/A699M **Full Title:** *Standard Specification for Steel, Carbon, Cold-Worked, for Springs and Other Applications* **Classification:** Class 2 **International Standard:** ASTM International (American Society for Testing and Materials) **Material Type:** Cold-worked, high-carbon steel wire and rod **Primary Processing:** Severe cold working (drawing or rolling) to achieve ultra-high strength without heat treatment **Key Characteristic:** Higher carbon content and greater cold work reduction than Class 1, resulting in superior strength for demanding spring applications --- ## 2. MATERIAL CHARACTERISTICS & MANUFACTURING ### 2.1 Manufacturing Process ASTM A699 Class 2 undergoes an intensive **cold deformation process** specifically engineered to maximize strength through strain hardening: **Production Sequence:** 1. **Starting Material:** Hot-rolled high-carbon steel rod (typically 0.70-0.90% C) 2. **Patent Treatment:** Optional intermediate heat treatment for microstructure refinement 3. **Severe Cold Reduction:** 50-70% area reduction through multiple drawing passes 4. **Surface Preparation:** Acid pickling and mechanical descaling between passes 5. **Final Processing:** Straightening, stress relieving (if specified), and surface finishing 6. **No Final Heat Treatment:** Properties achieved exclusively through cold work ### 2.2 Metallurgical Principles **Advanced Strain Hardening:** - Extreme dislocation density (10¹²-10¹³ cm⁻²) - Cellular dislocation substructure formation - Significant grain elongation and texture development - Very high residual compressive stresses at surface **Microstructural Features:** - **Phase Composition:** Essentially 100% cold-worked ferrite with fine cementite particles - **Grain Morphology:** Highly elongated in drawing direction - **Texture Components:** Strong <110> fiber texture parallel to drawing axis - **Carbide Distribution:** Cementite particles aligned in drawing direction --- ## 3. CHEMICAL COMPOSITION ### 3.1 Base Composition Requirements | Element | Composition Range (% by weight, maximum unless specified) | Metallurgical Function & Control | |---------|-----------------------------------------------------------|----------------------------------| | **Carbon (C)** | 0.70 - 0.90 | Primary strengthening element; higher range than Class 1 | | **Manganese (Mn)** | 0.60 - 0.90 | Enhances strain hardenability and strength | | **Phosphorus (P)** | 0.040 max | Strict control for ductility retention | | **Sulfur (S)** | 0.050 max | May be optimized for specific applications | | **Silicon (Si)** | 0.15 - 0.35 | Deoxidizer, solid solution strengthener | | **Copper (Cu)** | 0.20 max (when specified) | Optional for corrosion resistance | ### 3.2 Composition Optimization for Class 2 **Carbon Control:** - **Typical Target:** 0.75-0.85% for optimal balance - **Lower Range (0.70-0.75%):** Better ductility and formability - **Upper Range (0.85-0.90%):** Maximum achievable strength **Residual Element Limits:** - **Chromium (Cr):** ≤0.25% (tightly controlled) - **Nickel (Ni):** ≤0.25% (typically ≤0.15%) - **Molybdenum (Mo):** ≤0.10% (trace amounts only) - **Total Residuals:** Typically ≤0.60% maximum ### 3.3 Special Quality Variants 1. **Standard Class 2:** General spring applications 2. **Low-Temperature Class 2:** Enhanced toughness for cold environments 3. **High-Fatigue Class 2:** Optimized for cyclic loading applications 4. **Corrosion-Resistant Class 2:** With controlled copper addition --- ## 4. MECHANICAL PROPERTIES ### 4.1 Minimum Required Properties (ASTM A699) | Property | Minimum Requirement | Test Standard | Special Notes for Class 2 | |----------|---------------------|---------------|---------------------------| | **Tensile Strength** | 1400 MPa (203 ksi) minimum | ASTM A370 | Higher than Class 1 | | **Yield Strength (0.2% offset)** | Not specified; typically 85-92% of tensile | ASTM A370 | Very high yield ratio | | **Elongation in 10×Diameter** | 4% minimum | ASTM A370 | Reduced due to higher cold work | | **Reduction of Area** | 25% minimum | ASTM A370 | Critical for spring performance | | **Torsional Ductility** | Specified twists (if required) | Special test | Important for torsion springs | ### 4.2 Typical Property Ranges (Class 2) | Property | Typical Range | Comments | |----------|---------------|----------| | **Tensile Strength** | 1400-1700 MPa (203-247 ksi) | Varies with cold reduction | | **Yield Strength** | 1200-1500 MPa (174-218 ksi) | High yield-to-tensile ratio (0.85-0.92) | | **Modulus of Elasticity** | 200-205 GPa (29,000-29,700 ksi) | Slight increase longitudinally | | **Shear Modulus** | 79-81 GPa (11,450-11,750 ksi) | Critical for spring design | | **Elongation (Longitudinal)** | 4-7% | Minimum maintained despite high strength | | **Reduction of Area** | 25-35% | Indicates retained ductility | | **Hardness** | 40-47 HRC | Rockwell C scale | ### 4.3 Specialized Mechanical Properties **Fatigue Characteristics:** - **Rotating Bending Fatigue Limit:** 500-600 MPa (10⁷ cycles, polished) - **Fatigue Ratio:** 0.35-0.40 × tensile strength - **Surface Sensitivity:** Highly dependent on surface condition **Torsional Properties:** - **Torsional Strength:** 850-1000 MPa - **Torsional Modulus:** 78-80 GPa - **Torsional Ductility:** Typically 15-25 twists before failure **Anisotropy Characteristics:** - **Longitudinal vs. Transverse Strength:** 10-15% difference - **Shear Strength Directionality:** Minimal in torsion - **Impact Toughness:** Highly directional --- ## 5. PHYSICAL PROPERTIES | Property | Value | Conditions & Notes | |----------|-------|-------------------| | **Density** | 7.85 g/cm³ (0.284 lb/in³) | Unchanged by cold work | | **Modulus of Elasticity (E)** | 200-205 GPa (29,000-29,700 ksi) | Slight increase with cold work | | **Shear Modulus (G)** | 78-81 GPa (11,300-11,750 ksi) | Critical spring design parameter | | **Poisson's Ratio** | 0.285-0.295 | Slight anisotropy possible | | **Coefficient of Thermal Expansion** | 11.5 × 10⁻⁶/°C (6.4 × 10⁻⁶/°F) | 20-100°C range | | **Thermal Conductivity** | 46 W/(m·K) | At 100°C; decreases with carbon | | **Specific Heat** | 0.46 kJ/(kg·K) | At 20°C | | **Electrical Resistivity** | 0.19 μΩ·m | At 20°C; increases with cold work | | **Magnetic Properties** | Ferromagnetic | Strongly magnetic | | **Thermal Stability Limit** | 200°C (390°F) | Properties stable below this temperature | --- ## 6. FABRICATION CHARACTERISTICS ### 6.1 Forming & Shaping Limitations **Severe Limitations Due to Ultra-High Strength:** - **Cold Bending:** Minimum radius 10-12× thickness/diameter - **Hot Working:** Not permitted (destroys cold-worked properties) - **Straightening:** Limited, with risk of property alteration - **Coiling:** Possible for spring manufacture with proper equipment **Spring Manufacturing Specifics:** - **Coil Diameter:** Minimum 6-8× wire diameter - **Spring Index:** Typically 4-12 for practical manufacturing - **Set Removal:** Stress relief at 200-250°C recommended - **Surface Treatment:** Shot peening often applied after coiling ### 6.2 Machinability **Rating:** Poor (35-45% relative to B1112 steel) **Machining Guidelines:** | Operation | Recommended Parameters | Tool Considerations | |-----------|------------------------|---------------------| | **Turning** | 25-50 m/min, moderate feed | Carbide inserts with sharp edges | | **Drilling** | Low speed, high feed | Carbide drills, peck drilling | | **Milling** | 30-60 m/min, climb milling preferred | Carbide end mills, rigid setup | | **Grinding** | Recommended for final finishing | Aluminum oxide or CBN wheels | | **Threading** | Low speed, ample coolant | Carbide or HSS with proper geometry | ### 6.3 Heat Treatment Considerations **Critical Restriction:** No heat treatment above 300°C (570°F) **Permissible Thermal Exposures:** - **Stress Relief:** 200-250°C for 30-60 minutes - **Coating Cure:** ≤180°C for limited durations - **Service Temperature:** Continuous ≤150°C, peak ≤200°C - **Absolute Limit:** 300°C for property retention **Consequences of Overheating:** - **300-400°C:** Gradual property loss (10-30%) - **400-500°C:** Significant strength reduction (30-60%) - **>500°C:** Complete loss of cold-worked properties ### 6.4 Surface Treatments **Compatible Processes:** 1. **Shot Peening:** Highly recommended for fatigue applications 2. **Electroplating:** Zinc, cadmium, chromium (with proper preparation) 3. **Phosphating:** Excellent for corrosion protection and paint adhesion 4. **Organic Coatings:** Paints, powder coatings (cure ≤180°C) 5. **Vapor Deposition:** PVD coatings possible --- ## 7. PRIMARY APPLICATIONS ### 7.1 High-Performance Spring Applications | Application Category | Specific Components | Why Class 2 is Preferred | |----------------------|---------------------|--------------------------| | **Automotive Suspension** | Heavy-duty coil springs, stabilizer bars | Higher stress capability than Class 1 | | **Industrial Valves** | High-pressure valve springs, safety valve springs | Consistent performance at high loads | | **Aerospace** | Landing gear components, control system springs | High strength-to-weight ratio | | **Railway** | Primary suspension springs, draft gear springs | Fatigue resistance under dynamic loads | ### 7.2 Specialized Mechanical Components - **High-Strefasteners:** Special bolts, pins, clips requiring ultra-high strength - **Cutting Tools:** Non-powered cutting edges, blades - **Wear Components:** Bushings, bearings subject to high contact stress - **Agricultural:** Heavy-duty tillage tools, plow components ### 7.3 Precision Engineering Applications - **Medical Devices:** Surgical instrument components, orthopedic devices - **Optical Equipment:** Precision adjustment mechanisms - **Instrumentation:** High-sensitivity measuring devices - **Robotics:** High-stress actuator components ### 7.4 Defense & Security Applications - **Firearms:** Spring components requiring consistent performance - **Security Systems:** High-reliability locking mechanisms - **Military Vehicles:** Suspension and weapon system components - **Safety Systems:** Emergency release mechanisms --- ## 8. COMPARATIVE ANALYSIS ### 8.1 Within ASTM A699 Family | Property | Class 1 | **Class 2** | Class 3 | |----------|---------|-------------|---------| | **Carbon Range** | 0.65-0.85% | **0.70-0.90%** | 0.85-1.05% | | **Min Tensile Strength** | 1300 MPa | **1400 MPa** | 1500 MPa | | **Typical Hardness** | 38-45 HRC | **40-47 HRC** | 42-50 HRC | | **Cold Reduction** | 30-50% | **50-70%** | 60-80% | | **Relative Cost** | 1.00 | **1.08-1.15** | 1.15-1.25 | | **Primary Use** | General springs | **High-stress springs** | Maximum strength applications | ### 8.2 Comparison with Heat-Treated Alternatives | Aspect | ASTM A699 Class 2 (Cold-worked) | SAE 1080 (Oil-quenched) | ASTM A401 (Cr-V) | |--------|---------------------------------|-------------------------|------------------| | **Strength Consistency** | Excellent | Batch dependent | Good | | **Production Method** | Cold working only | Heat treatment required | Heat treatment required | | **Distortion Risk** | None | Significant | Moderate | | **Anisotropy** | High | Low | Low | | **Fatigue Performance** | Very Good (with peening) | Excellent | Superior | | **Cost Efficiency** | High for suitable applications | Moderate | High | ### 8.3 International Comparison | Standard | Equivalent Grade | Key Differences | |----------|------------------|-----------------| | **EN 10270-1** | SH (Cold-drawn) | Similar concept, different classification | | **JIS G 4801** | SWP-B | Similar strength level | | **ISO 8458-2** | Class C | International classification | | **GB/T 4357** | Grade D | Chinese cold-drawn spring steel | --- ## 9. DESIGN CONSIDERATIONS ### 9.1 Spring Design Guidelines **Critical Design Parameters:** - **Maximum Shear Stress:** ≤0.45 × tensile strength - **Spring Rate:** Calculate using actual shear modulus - **Set Allowance:** Design for 5-10% initial set - **Fatigue Life:** Design for ≤0.35 × tensile as alternating stress **Surface Condition Requirements:** - **Polished Surfaces:** For maximum fatigue resistance - **Shot Peening:** Mandatory for high-cycle fatigue applications - **Coating Compatibility:** Ensure thermal limits respected - **Stress Raisers:** Minimize sharp transitions and notches ### 9.2 Directional Property Utilization **Optimal Orientation Strategies:** - **Primary Load Direction:** Align with drawing direction - **Shear Loading:** Less sensitive to orientation - **Multi-axial Stress:** Conservative design approach required - **Notch Sensitivity:** Higher transverse to drawing direction ### 9.3 Temperature Considerations **Service Temperature Guidelines:** - **Ideal Range:** -40°C to +150°C (-40°F to +300°F) - **Upper Limit:** 200°C (390°F) for short durations - **Property Stability:** Excellent below 150°C (300°F) - **Thermal Cycling:** Limited data; conservative approach recommended --- ## 10. QUALITY ASSURANCE & TESTING ### 10.1 Standard Testing Protocol | Test | Frequency | Specimen Requirements | Acceptance Criteria | |------|-----------|------------------------|---------------------| | **Chemical Analysis** | Each heat | Representative sample | Meets Class 2 composition | | **Tensile Test** | Each lot | Full cross-section specimen | Min 1400 MPa tensile, 4% elongation | | **Hardness Test** | Statistical sampling | Multiple locations | Consistent within specified range | | **Surface Inspection** | 100% visual | As produced | Free from defects, seams, cracks | | **Dimensional Check** | Each coil/lot | Critical dimensions | Within specified tolerances | ### 10.2 Specialized Testing (When Specified) - **Torsion Testing:** Number of twists to failure - **Bend Testing:** Mandrel bend tests for ductility - **Fatigue Testing:** Rotating beam or axial fatigue tests - **Decarburization Depth:** Maximum 1.5% of diameter or 0.20mm - **Non-destructive Testing:** Ultrasonic or eddy current for internal defects ### 10.3 Certification & Traceability - **Mill Test Certificate:** Comprehensive test results - **Heat/Lot Traceability:** Complete production history - **Compliance Statement:** Verification to ASTM A699 Class 2 - **Additional Certifications:** Available for special requirements --- ## 11. ORDERING INFORMATION ### 11.1 Specification Format ``` Material: ASTM A699, Class 2 Form: [Round wire, flat wire, rod] - specify Dimensions: [Diameter/Width × Thickness] and tolerances Condition: Cold worked, as drawn Surface Finish: [Bright, pickled, phosphated] - specify Special Requirements: [Straightness, packaging, testing] Quantity: [Weight in kg/lb or length in m/ft] Application: [For information purposes] ``` ### 11.2 Available Forms & Tolerances | Form | Size Range | Standard Tolerances | |------|------------|---------------------| | **Round Wire** | 1.0-20.0 mm diameter | ±0.03mm (precision), ±0.08mm (commercial) | | **Flat Wire** | 0.5-8.0 mm thick, 2-60 mm wide | Thickness ±0.025mm, Width ±0.08mm | | **Rods** | 6-60 mm diameter | Diameter ±0.08mm, Straightness 0.5mm/m | | **Coils** | All wire forms | Coil weight typically 200-1000kg | ### 11.3 Surface Condition Options 1. **Bright Drawn:** Smooth, as-drawn surface 2. **Pickled & Oiled:** Scale-free, corrosion protected 3. **Phosphated:** For enhanced corrosion resistance 4. **Coated:** Various organic or metallic coatings available 5. **Polished:** Special finish for critical applications --- ## 12. TECHNICAL SUPPORT RESOURCES ### 12.1 Design Assistance Available - **Spring Design Software:** From major manufacturers - **Application Engineering:** Supplier technical support - **Failure Analysis:** For performance issues - **Testing Services:** Third-party laboratory testing ### 12.2 Industry Standards & References - **SAE Spring Design Manual:** Comprehensive design guidelines - **ASTM Standards:** Related material and test specifications - **Spring Manufacturers Institute:** Technical publications - **Machinery's Handbook:** Design and manufacturing data --- ## 13. FABRICATION BEST PRACTICES ### 13.1 Handling & Storage Guidelines - **Handling:** Avoid bending or kinking; use proper equipment - **Storage:** Dry, controlled environment to prevent corrosion - **Identification:** Maintain heat/lot segregation throughout - **Shelf Life:** Indefinite with proper storage conditions ### 13.2 Manufacturing Process Control 1. **Tooling Maintenance:** Regular inspection and replacement 2. **Process Monitoring:** Temperature control during any operations 3. **Quality Checks:** In-process inspection critical 4. **Documentation:** Complete process records for traceability ### 13.3 Spring-Specific Fabrication - **Coiling Equipment:** Properly maintained and calibrated - **Stress Relief:** Controlled thermal treatment if specified - **Surface Enhancement:** Shot peening after coiling - **Final Inspection:** 100% dimensional and performance testing --- ## SUMMARY **ASTM A699 Class 2** represents an **ultra-high-strength, cold-worked carbon steel** specifically engineered for demanding spring applications where maximum strength and reliability are critical. The severe cold working process produces exceptional strength levels while maintaining sufficient ductility for spring performance. **Key Advantages of Class 2:** 1. **Exceptional Strength:** 1400+ MPa tensile strength without heat treatment 2. **Consistent Properties:** Uniform mechanical characteristics 3. **Good Fatigue Resistance:** Particularly with proper surface treatment 4. **No Distortion Issues:** Eliminates heat treatment distortion problems 5. **Cost Efficiency:** For applications suited to cold-worked properties **Critical Limitations:** 1. **Severe Forming Restrictions:** Limited post-production formability 2. **High Anisotropy:** Significant directional property variation 3. **Temperature Sensitivity:** Properties degrade above 200°C 4. **Machining Challenges:** Requires specialized techniques and tooling **Optimal Application Scenarios:** - High-stress spring applications where cold working is final operation - Components requiring maximum strength without subsequent heat treatment - Applications where dimensional consistency is critical - Production environments seeking reliable, repeatable material properties **Selection Decision Factors:** 1. Confirm that cold-worked properties meet all application requirements 2. Evaluate directional loading vs. material anisotropy 3. Consider total manufacturing cost including any required processing 4. Assess service temperature exposure 5. Verify availability in required form, size, and quantity **Final Recommendation:** ASTM A699 Class 2 is recommended for experienced engineers and manufacturers working with high-performance spring applications. It provides superior strength for demanding applications but requires thorough understanding of its unique characteristics and careful attention to design, fabrication, and quality control practices. --- **IMPORTANT CONSIDERATIONS:** 1. This material cannot be heat treated; it must be used as-supplied 2. Design must account for significant property anisotropy 3. Temperature control during all processing is essential 4. Consultation with material suppliers is strongly recommended 5. Prototype testing advisable for critical applications **DISCLAIMER:** This technical information is provided for general guidance. For specific applications, consult the latest edition of ASTM A699/A699M, relevant design codes, and qualified engineering professionals. Material properties may vary by manufacturer and production batch. Always review certified mill test reports for critical applications. -:- For detailed product information, please contact sales. -: ASTM A699 Steel, class 2 Specification Dimensions Size： Diameter 20-1000 mm Length <5954 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 A699 Steel, class 2 Properties -:- For detailed product information, please contact sales. -:

Spherical ASTM A699 Steel Powder, class 2 Particle Size Description -:- For detailed product information, please contact sales. -: Applications of Spherical ASTM A699 Steel Powder, class 2 -:- For detailed product information, please contact sales. -: -:- For detailed product information, please contact sales. -: Applications of ASTM A699 Steel Spherical Powder, class 2 -:- For detailed product information, please contact sales. -: Chemical Identifiers ASTM A699 Steel Spherical Powder, class 2 -:- For detailed product information, please contact sales. -:

Packing of ASTM A699 Steel Spherical Powder, class 2 -:- 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 Spherical Powder 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 2425 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