AISI 1151 Steel, Cold Drawn,UNS G11510

AISI 1151 Steel, Cold Drawn Bar (UNS G11510) Product Information -:- For detailed product information, please contact sales. -: AISI 1151 Steel, Cold Drawn Bar (UNS G11510) Synonyms -:- For detailed product information, please contact sales. -:

AISI 1151 Steel, Cold Drawn Bar (UNS G11510) Product Information -:- For detailed product information, please contact sales. -: # **Product Technical Data Sheet: AISI 1151 Cold Drawn Steel Bar** **Product Designation:** AISI 1151 / SAE 1151 / UNS G11510 **Condition:** Cold Drawn, Stress Relieved (Typical) **Form:** Precision Round Bar, Hexagonal, Square **Size Range:** 6-75 mm diameter (0.25-3 inches) **Surface Finish:** Smooth, Scale-Free **Key Characteristics:** Enhanced Strength, Improved Dimensional Accuracy, Superior Surface Quality --- ## **1. Overview** AISI 1151 cold drawn steel represents a **precision-engineered version** of this medium-carbon manganese steel, offering significantly improved mechanical properties and dimensional characteristics over its hot-rolled counterpart. The **cold drawing process** involves pulling hot-rolled bars through tungsten carbide or diamond dies at room temperature, inducing substantial work hardening and creating a smooth, scale-free surface. This process transforms the material's microstructure, aligning grains in the drawing direction and developing favorable residual stress patterns. For AISI 1151, the combination of its inherent manganese-enhanced hardenability with cold work strengthening creates a material particularly suitable for **precision components, shafts, and fasteners** requiring excellent strength, dimensional accuracy, and good surface finish without subsequent heat treatment. ## **2. Chemical Composition (Weight %)** *Per SAE J403 and ASTM A108 specifications* | Element | Content Range (%) | Target Value (%) | Effect on Cold Drawing Response | |---------|------------------|-----------------|---------------------------------| | **Carbon (C)** | 0.48 - 0.55 | 0.52 | Provides strong response to work hardening, forms pearlite/martensite network | | **Manganese (Mn)** | 1.00 - 1.30 | 1.15 | Enhances work hardening rate, improves strength retention after drawing | | **Silicon (Si)** | 0.15 - 0.35 | 0.25 | Provides solid solution strengthening, increases work hardening capability | | **Phosphorus (P)** | ≤ 0.040 | 0.020 | Strictly controlled to prevent cold brittleness | | **Sulfur (S)** | 0.08 - 0.13 | 0.10 | Forms MnS inclusions that aid chip control during subsequent machining | | **Iron (Fe)** | Balance | Balance | Matrix element | **Cold Drawing Chemistry Optimization:** - **Carbon Content:** Optimal for balancing work hardening response with ductility - **Manganese Level:** High enough to enhance strength but not so high as to cause excessive springback - **Sulfur Control:** Lower than 1100 series for better transverse properties - **Deoxidation:** Fully killed steel for consistent drawing behavior ## **3. Physical Properties (Cold Drawn Condition)** | Property | Value | Unit | Characteristics | |----------|-------|------|-----------------| | **Density** | 7.85 | g/cm³ | At 20°C | | **Modulus of Elasticity** | 200 - 205 | GPa | 29.0 - 29.7 × 10⁶ psi | | **Shear Modulus** | 78 - 80 | GPa | 11.3 - 11.6 × 10⁶ psi | | **Poisson's Ratio** | 0.29 | - | - | | **Thermal Conductivity** | 44.0 - 46.0 | W/m·K | At 100°C (slightly reduced due to cold work) | | **Specific Heat Capacity** | 475 - 485 | J/kg·K | At 20°C | | **Coefficient of Thermal Expansion** | 11.5 × 10⁻⁶ | /°C | 20-100°C range | | **Electrical Resistivity** | 0.22 - 0.24 | μΩ·m | At 20°C (increased due to dislocation density) | | **Surface Roughness** | 0.8 - 3.2 μm Ra | - | Typical as-drawn condition | ## **4. Mechanical Properties (Cold Drawn)** *Properties vary with degree of cold work and final stress relief* | Property | Light Drawn (10-15% RA) | Medium Drawn (15-25% RA) | Heavy Drawn (25-35% RA) | Test Standard | |----------|-------------------------|--------------------------|-------------------------|---------------| | **Tensile Strength** | 700 - 800 MPa | 750 - 850 MPa | 800 - 900 MPa | ASTM E8/E8M | | **Yield Strength (0.2%)** | 550 - 650 MPa | 600 - 700 MPa | 650 - 750 MPa | ASTM E8/E8M | | **Elongation (in 50mm)** | 15 - 20% | 12 - 17% | 10 - 15% | ASTM E8/E8M | | **Reduction of Area** | 45 - 55% | 40 - 50% | 35 - 45% | ASTM E8/E8M | | **Hardness** | 22 - 28 HRC | 24 - 30 HRC | 26 - 32 HRC | ASTM E18 | | **Impact Energy (CVN)** | 25 - 40 J | 20 - 35 J | 15 - 30 J | ASTM E23 | | **Fatigue Strength** | 320 - 380 MPa | 350 - 400 MPa | 380 - 430 MPa | R=-1, 10⁷ cycles | | **Machinability Rating** | 55 - 60% | 50 - 55% | 45 - 50% | vs. 1212 steel | **Typical Commercial Properties:** - **Minimum Yield Strength:** 585 MPa (85 ksi) commonly guaranteed - **Hardness Range:** 24-30 HRC for standard commercial product - **Straightness:** ≤0.5 mm per 300 mm length - **Dimensional Tolerance:** Typically ±0.05-0.10 mm for diameters up to 25 mm ## **5. Cold Drawing Process & Microstructure** ### **Manufacturing Sequence:** 1. **Hot Rolling:** Initial production to oversize dimensions 2. **Pickling:** Acid cleaning to remove mill scale 3. **Phosphating/Lubrication:** Surface preparation for drawing 4. **Cold Drawing:** Single or multiple passes through carbide dies 5. **Stress Relieving:** 300-400°C to reduce residual stresses (optional but common) 6. **Straightening:** Rotary or gag straightening 7. **Cutting:** Precision saw cutting to length ### **Microstructural Evolution:** - **Pre-drawing:** Equiaxed ferrite-pearlite structure - **During Drawing:** Grains elongate in drawing direction, dislocation density increases - **Final Structure:** Fibrous grain structure with high dislocation density - **Texture Development:** Strong <110> fiber texture parallel to drawing axis - **Inclusion Alignment:** MnS inclusions elongated in drawing direction - **Surface Layer:** Work-hardened to depth of 0.05-0.15 mm ### **Degree of Cold Work Effects:** | Reduction Area | Typical Applications | Microstructural Changes | |----------------|---------------------|-------------------------| | **10-15%** | General machining stock | Moderate work hardening | | **15-25%** | Precision shafts, fasteners | Significant grain elongation | | **25-35%** | High-strength components | Near-maximum dislocation density | ## **6. Key Characteristics & Advantages** ### **Cold Drawn Advantages:** 1. **Enhanced Strength:** 20-40% higher yield strength than hot rolled 2. **Superior Dimensional Accuracy:** Tight tolerances (±0.05-0.10 mm typical) 3. **Excellent Surface Finish:** Scale-free, smooth surface (Ra 0.8-3.2 μm) 4. **Improved Straightness:** ≤0.5 mm/300 mm typically guaranteed 5. **Minimal Machining Required:** Often used as-machined without stock removal ### **Comparison with Hot Rolled AISI 1151:** | Property | Hot Rolled 1151 | **Cold Drawn 1151** | Improvement | |----------|-----------------|---------------------|-------------| | **Yield Strength** | 345-450 MPa | **550-750 MPa** | 60-100% | | **Dimensional Tolerance** | ±0.8-1.5 mm | **±0.05-0.10 mm** | 90-95% | | **Surface Finish** | Ra 12.5-25 μm | **Ra 0.8-3.2 μm** | 85-95% | | **Straightness** | ≤2.0 mm/m | **≤0.5 mm/m** | 75% | | **Decarburization** | 0.1-0.4 mm | **None** | 100% | | **Cost Factor** | 1.0 | **1.3-1.6** | - | ## **7. Applications** ### **Primary Applications:** **Precision Shafting & Axles:** - Machine tool spindles and lead screws - Automotive steering columns - Pump and compressor shafts - Drive shafts for industrial equipment **Fastener Manufacturing:** - High-strength bolt stock (Grade 8.8 and higher) - Special fastener production - Studs and threaded rods - Precision pins and dowels **Automotive Components:** - Transmission shafts - Suspension components - Brake system parts - Engine accessory shafts **Industrial Components:** - Linear motion shafts - Guide rods and columns - Hydraulic cylinder rods - Bearing journals and races ### **Size-Specific Applications:** | Diameter Range | Typical Applications | |----------------|---------------------| | **6-12 mm** | Small fasteners, precision pins, instrument parts | | **12-25 mm** | Automotive shafts, machine tool components, general fasteners | | **25-50 mm** | Drive shafts, hydraulic rods, industrial shafts | | **50-75 mm** | Heavy equipment shafts, large fasteners, structural components | ## **8. International Standards & Equivalents** ### **Material Standards:** | Standard System | Designation | Specification | |----------------|-------------|---------------| | **AISI/SAE (USA)** | 1151 | SAE J403, J404 | | **UNS (USA)** | **G11510** | Unified Numbering System | | **ASTM (USA)** | **A108** | Standard for Steel Bars, Carbon, Cold-Finished | | **ASTM (USA)** | A29/A29M | General Requirements for Steel Bars | | **ISO** | **ISO 683-1** | C55E (similar composition) | | **DIN (Germany)** | 1.1208 | C55E | | **EN (Europe)** | **EN 10083-2** | C55E | | **JIS (Japan)** | S55C | Japanese equivalent | ### **Cold Drawn Specific Standards:** - **ASTM A108:** Standard Specification for Steel Bars, Carbon, Cold-Finished - **ISO 286-2:** ISO system of limits and fits for cold finished products - **SAE J1397:** Surface Finish of Cold Finished Carbon and Alloy Steel Bars ## **9. Quality Assurance & Testing** ### **Standard Testing Requirements:** 1. **Chemical Analysis:** Full elemental analysis for each heat 2. **Mechanical Testing:** Tensile tests from each cold drawing lot 3. **Hardness Testing:** Multiple point verification 4. **Surface Inspection:** Visual and roughness measurement 5. **Dimensional Verification:** Full dimensional survey ### **Cold Drawn Specific Quality Features:** - **Decarb-Free Guarantee:** Standard for cold drawn products - **Precision Tolerances:** Typically h9 or h10 tolerance grades - **Superior Straightness:** Often 2-3 times better than ASTM minimums - **Surface Integrity:** No scale, pits, or major imperfections ### **Commercial Quality Levels:** | Quality Level | Tolerance | Straightness | Surface Finish | Typical Use | |--------------|-----------|--------------|----------------|-------------| | **Commercial** | ±0.10 mm | ≤0.5 mm/m | Ra 1.6-3.2 μm | General machining | | **Precision** | ±0.05 mm | ≤0.3 mm/m | Ra 0.8-1.6 μm | Precision components | | **Special** | ±0.02 mm | ≤0.2 mm/m | Ra 0.4-0.8 μm | High-precision applications | ## **10. Design & Manufacturing Guidelines** ### **Design Advantages:** - **Minimal Machining Allowances:** Often only 0.1-0.3 mm per side required - **Reduced Fixturing Needs:** Good straightness simplifies setup - **Predictable Properties:** Consistent material response - **Good Fatigue Performance:** Smooth surface reduces stress concentrations ### **Machining Considerations:** - **Tool Selection:** Carbide tools recommended for production work - **Cutting Parameters:** Moderate speeds (30-50 m/min) due to work hardening - **Chip Control:** MnS inclusions provide reasonable chip breaking - **Work Hardening:** Account for potential hardness increase during machining ### **Recommended Processing:** | Operation | Speed (m/min) | Feed (mm/rev) | Depth of Cut (mm) | Notes | |-----------|--------------|---------------|-------------------|-------| | **Turning** | 35-50 | 0.15-0.25 | 1.0-3.0 | Carbide tools preferred | | **Milling** | 30-45 | 0.08-0.20/tooth | 1.0-2.5 | Climb milling recommended | | **Drilling** | 20-35 | 0.10-0.25/rev | - | Peck drilling for deep holes | | **Threading** | 15-25 | - | - | Use sharp, properly ground tools | ### **Heat Treatment After Cold Drawing:** **Stress Relieving (Common):** - **Temperature:** 300-400°C (575-750°F) - **Time:** 60-90 minutes - **Purpose:** Reduce residual stresses, improve dimensional stability **Full Heat Treatment (If Required):** - **Normalizing:** 870-900°C to restore equiaxed structure - **Quenching & Tempering:** 830-850°C austenitize, then quench and temper - **Note:** Cold work effects eliminated above 650°C ### **Economic Advantages:** - **Reduced Machining:** Less stock removal required - **Lower Reject Rates:** Better dimensional control - **Faster Production:** Less time spent on rough machining - **Material Savings:** Closer to finished size reduces waste ### **Limitations & Considerations:** - **Anisotropic Properties:** Significant directional differences - **Size Limitations:** Maximum practical diameter ~75-100 mm - **Work Hardening:** Can complicate subsequent machining - **Springback:** Must be considered in bending operations - **Maximum Service Temperature:** ~150°C to maintain cold work benefits --- **Technical Summary:** AISI 1151 cold drawn steel bar represents a significant upgrade from the hot rolled version, offering enhanced mechanical properties, superior dimensional accuracy, and excellent surface quality. The cold drawing process leverages the material's good work hardening response (from its 0.48-0.55% carbon and 1.00-1.30% manganese content) to create a product suitable for precision applications where strength and dimensional control are critical. While more expensive than hot rolled material, the benefits in reduced machining, improved consistency, and better performance often justify the additional cost for many applications. **Application Selection Guidelines:** - **Choose cold drawn 1151 when:** Precision dimensions, good surface finish, and enhanced strength are required - **Consider hot rolled when:** Cost is primary concern and extensive machining is planned - **Best for:** Shafts, fasteners, and precision components in the 6-75 mm diameter range - **Alternative materials:** 1144 for better machinability, 4140 for higher hardenability **Industry Best Practices:** 1. **Specify Degree of Cold Work:** Based on required properties 2. **Request Stress Relief:** For complex parts requiring dimensional stability 3. **Order Close to Finished Size:** Minimize machining 4. **Verify Material Certification:** Ensure proper processing and testing **Technical Note on Property Directionality:** Cold drawn AISI 1151 exhibits significant anisotropic properties: - **Longitudinal Properties:** Excellent strength and ductility - **Transverse Properties:** Reduced (typically 60-70% of longitudinal values) - **Design Consideration:** Load paths should align with drawing direction where possible **Future Processing Options:** - Direct machining to finished dimensions - Further cold working (thread rolling, cold forging) - Heat treatment for enhanced properties - Surface treatments (plating, nitriding) **Disclaimer:** This technical data sheet provides typical values for cold drawn AISI 1151. Actual properties depend on degree of cold work, stress relief conditions, and manufacturer practices. The material exhibits anisotropic behavior that must be considered in design. For critical applications, consultation with material suppliers and prototype testing are recommended. Cold drawn properties can be affected by subsequent heat exposure above 150°C. Always verify material certification and conduct application-specific testing when properties are critical. -:- For detailed product information, please contact sales. -: AISI 1151 Steel, Cold Drawn Bar (UNS G11510) Specification Dimensions Size： Diameter 20-1000 mm Length <6160 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. -: AISI 1151 Steel, Cold Drawn Bar (UNS G11510) Properties -:- For detailed product information, please contact sales. -:

Applications of AISI 1151 Steel, Cold Drawn Bar (UNS G11510) -:- For detailed product information, please contact sales. -: Chemical Identifiers AISI 1151 Steel, Cold Drawn Bar (UNS G11510) -:- For detailed product information, please contact sales. -:

Packing of AISI 1151 Steel, Cold Drawn Bar (UNS G11510) -:- 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 2631 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