AISI 8650H Steel, normalized

AISI 8650H Steel, normalized Product Information -:- For detailed product information, please contact sales. -: AISI 8650H Steel, normalized Synonyms -:- For detailed product information, please contact sales. -:

AISI 8650H Steel, normalized Product Information -:- For detailed product information, please contact sales. -: # Technical Data Sheet: AISI 8650H Alloy Steel ## H-Grade, Normalized Condition --- ### 1. Product Identification **Designation:** AISI 8650H / UNS H86500 **Condition:** Normalized **Material Classification:** Hardenability-Controlled Nickel-Chromium-Molybdenum Medium-High Carbon Alloy Steel **Key Characteristics:** AISI 8650H in the normalized condition represents a refined heat-treated state specifically engineered for manufacturing components requiring consistent properties and predictable response to subsequent processing. The "H" designation ensures controlled hardenability within SAE J1268 bands, while the normalizing treatment refines the grain structure, homogenizes the microstructure, and improves mechanical properties over the as-rolled condition. This condition provides an optimal balance of strength, hardness, and machinability, making it suitable for either direct use in moderate-strength applications or as an ideal starting condition for further heat treatment processes. --- ### 2. International Standards Compliance **Primary Specifications:** - **UNS:** H86500 - **ASTM Standards:** - **A304:** Steel Bars, Alloy, Subject to End-Quench Hardenability Requirements - **A914/A914M:** Steel Bars Subject to Restricted Hardenability Requirements - **A29/A29M:** Steel Bars, Carbon and Alloy, Hot-Wrought and Cold-Finished (Normalized Condition) - **SAE/AISI Standards:** - **SAE J1268:** Hardenability Bands for H-Grade Steels - **SAE J404:** Chemical Compositions of SAE Alloy Steels - **ISO Standards:** - **ISO 683-11:** Heat-treatable steels, alloy steels and free-cutting steels - **European Standards:** - **EN 10083-3:** Steels for quenching and tempering - Similar to normalized 1.6546H (34CrNiMo6H) **Normalizing Specification:** - Full normalizing per standard industry practice - Hardness typically controlled to 207-255 HB - Microstructural requirements: Uniform fine-grained structure - Compliance with ASTM A29 normalized condition requirements --- ### 3. Chemical Composition (H-Grade Controlled) **Guaranteed Composition Ranges (Weight %):** | Element | H-Grade Range | Typical Value | H-Grade Control Purpose | Normalizing Significance | |---------|---------------|---------------|-------------------------|--------------------------| | **Carbon (C)** | 0.47 - 0.54% | 0.50% | Controlled for consistent hardenability | Highest in 86xx series; determines normalized hardness | | **Manganese (Mn)** | 0.70 - 1.05% | 0.87% | Primary hardenability control element | Affects transformation during air cooling | | **Silicon (Si)** | 0.15 - 0.35% | 0.25% | Controlled for consistent effects | Deoxidizer; strengthens ferrite | | **Nickel (Ni)** | 0.35 - 0.75% | 0.55% | Controlled within narrower bands | Promotes grain refinement during normalizing | | **Chromium (Cr)** | 0.35 - 0.65% | 0.50% | Ensures consistent hardenability depth | Forms carbides; affects cooling transformation | | **Molybdenum (Mo)** | 0.15 - 0.25% | 0.20% | Critical for temper embrittlement control | Refines grain structure; enhances hardenability | | **Phosphorus (P)** | ≤ 0.035% | 0.020% | Minimized for improved toughness | Controlled for consistency | | **Sulfur (S)** | ≤ 0.040% | 0.025% | Standard grade; may be controlled | May be increased for improved machinability variants | | **Iron (Fe)** | Balance | Balance | Matrix element | - | **H-Grade Control Advantages for Normalized Material:** - Consistent normalizing response batch-to-batch - Predictable mechanical properties after normalizing - Uniform microstructure regardless of production heat - Reliable hardenability for subsequent heat treatment - Reduced testing requirements due to statistical control **Optimal Chemistry for Normalized Condition:** - Carbon: 0.48-0.52% (balanced for strength and machinability) - Manganese: 0.85-0.95% (optimized for transformation control) - Nickel: 0.50-0.60% (enhances toughness in normalized state) - Molybdenum: 0.18-0.22% (ensures grain refinement) --- ### 4. Normalizing Process & Microstructure **Standard Normalizing Process:** **Heating Cycle:** - **Temperature:** 870-900°C (1600-1650°F) - typically 885°C (1625°F) - **Soaking Time:** 30-60 minutes per inch of thickness minimum - **Atmosphere:** Air or protective atmosphere to limit decarburization (<0.25 mm) - **Temperature Uniformity:** ±10°C within furnace work zone **Cooling Cycle:** - **Medium:** Still air or controlled air circulation - **Cooling Rate:** Approximately 20-50°C/minute (36-90°F/minute) through transformation - **Cooling Uniformity:** Ensured by proper spacing and air flow - **Final Cooling:** To room temperature **Microstructural Characteristics:** **As-Normalized Structure:** - **Primary Constituents:** Fine pearlite with proeutectoid ferrite at grain boundaries - **Grain Size:** ASTM 6-8 (refined from as-rolled condition) - **Carbide Distribution:** Fine, uniform lamellar carbides in pearlite colonies - **Banding:** Significantly reduced compared to as-rolled condition - **Inclusion Morphology:** More rounded and less elongated **H-Grade Microstructural Advantages:** - More consistent microstructure across production batches - Uniform grain size distribution - Reduced chemical segregation - Predictable response to subsequent heat treatment **Section Size Effects (Typical):** - **Small Sections (<25 mm):** Primarily fine pearlite with minimal ferrite - **Medium Sections (25-75 mm):** Mixed pearlite-ferrite structure, uniform - **Large Sections (>75 mm):** Potential for coarser structure near center **Normalizing Objectives Achieved:** 1. Grain refinement for improved toughness 2. Homogenization of microstructure and chemistry 3. Stress relief from previous hot working 4. Improvement of machinability over as-rolled condition 5. Creation of consistent starting condition for further processing --- ### 5. Mechanical Properties (Normalized Condition) **Typical Properties for Various Section Sizes:** | Property | 25 mm (1") Diameter | 50 mm (2") Diameter | 75 mm (3") Diameter | Test Standard | |----------|---------------------|---------------------|---------------------|---------------| | **Hardness** | 217-241 HB | 207-235 HB | 197-229 HB | ASTM E10 | | **Tensile Strength** | 760-860 MPa | 690-790 MPa | 620-720 MPa | ASTM A370 | | **Yield Strength (0.2%)** | 515-620 MPa | 450-550 MPa | 400-500 MPa | ASTM A370 | | **Elongation (in 50 mm)** | 18-24% | 19-25% | 20-26% | ASTM A370 | | **Reduction of Area** | 45-60% | 47-62% | 49-64% | ASTM A370 | | **Charpy V-Notch (20°C)** | 40-70 J | 42-72 J | 44-74 J | ASTM E23 | | **Charpy V-Notch (-18°C)** | 25-45 J | 27-47 J | 29-49 J | ASTM E23 | | **Fatigue Strength (10⁷)** | 350-420 MPa | 340-410 MPa | 330-400 MPa | ASTM E466 | | **Machinability Rating** | 50-55% | - | - | vs. B1112 steel | **H-Grade Property Consistency:** - **Batch-to-Batch Variation:** ≤6% for strength properties - **Cross-Section Uniformity:** Hardness variation ≤15 HB points - **Statistical Control:** 99.7% within ±2σ of target values - **Testing Reduction:** Sample frequency reduced by 30-40% **Physical Properties:** | Property | Value | Units | Conditions | |----------|-------|-------|------------| | **Density** | 7.85 | g/cm³ | At 20°C | | **Melting Range** | 1410-1455 | °C | Liquidus to solidus | | **Thermal Conductivity** | 41.0 | W/m·K | At 100°C | | **Specific Heat Capacity** | 460 | J/kg·K | At 100°C | | **Coefficient of Thermal Expansion** | 11.5 × 10⁻⁶ | /°C | 20-100°C range | | **Modulus of Elasticity** | 205 | GPa | At 20°C | | **Shear Modulus** | 80 | GPa | At 20°C | | **Electrical Resistivity** | 0.24 | μΩ·m | At 20°C | **Fatigue Properties:** - **Endurance Limit:** 40-45% of tensile strength - **Notch Sensitivity Factor:** q = 0.70-0.80 - **Surface Finish Effect:** Significant on fatigue performance - **Mean Stress Effect:** Follows modified Goodman relationship --- ### 6. Hardenability Characteristics **SAE J1268 Hardenability Band for 8650H:** | Distance from Quenched End | Rockwell C Hardness Range (As-Quenched) | Normalized Structure Effect | |----------------------------|-----------------------------------------|----------------------------| | 1.5 mm (1/16") | 49-61 HRC | Fine grain improves hardenability | | 5.0 mm (3/16") | 45-57 HRC | Uniform structure enhances consistency | | 9.5 mm (3/8") | 39-51 HRC | Reduced segregation improves properties | | 12.7 mm (1/2") | 36-48 HRC | - | | 25.4 mm (1") | 27-39 HRC | - | **Advantages of Normalized Starting Condition for Hardening:** 1. **Uniform Austenitizing:** Consistent transformation during heating 2. **Reduced Distortion:** More stable than as-rolled material 3. **Predictable Growth:** Consistent dimensional changes 4. **Improved Response:** Better hardenability than annealed condition 5. **Reduced Risk:** Lower probability of quenching cracks **Expected Hardening Results from Normalized State:** - More consistent case depth in surface hardening - Uniform core properties in through-hardening - Reduced property scatter in final hardened component - Better dimensional control during heat treatment --- ### 7. Machinability & Formability **Machinability Characteristics:** - **Rating:** 50-55% of B1112 free-machining steel - **Tool Materials:** Carbide recommended for production; HSS suitable - **Recommended Cutting Parameters:** - **Turning:** 60-100 m/min (200-330 SFM) with carbide - **Turning:** 30-50 m/min (100-165 SFM) with HSS - **Drilling:** 20-30 m/min (65-100 SFM) with HSS drills - **Milling:** 40-60 m/min (130-200 SFM) with carbide - **Feed Rates:** 0.15-0.30 mm/rev (0.006-0.012 ipr) - **Depth of Cut:** Up to 5 mm (0.200") depending on setup - **Chip Formation:** Continuous chips; chip breakers recommended - **Surface Finish:** Can achieve Ra 1.6-3.2 μm (63-125 μin) - **Coolant:** Recommended for optimal results **Comparison with Other Conditions:** - **vs. Annealed:** Slightly lower machinability but better dimensional stability - **vs. As-rolled:** Better machinability and more consistent properties - **vs. Quenched & Tempered:** Much better machinability but lower strength **Forming & Fabrication:** - **Cold Bending:** Fair for moderate bends (minimum bend radius ~3t) - **Hot Forming:** Recommended for significant deformation - **Welding:** Possible with precautions; requires preheat and post-heat treatment - **Machining Allowances:** Standard allowances apply **H-Grade Machining Advantages:** - Consistent tool life across production batches - Predictable machining forces and power requirements - Reduced trial runs for new material batches - More reliable production scheduling --- ### 8. Material Characteristics in Normalized State **Advantages of Normalized AISI 8650H:** 1. **Improved Mechanical Properties:** Higher strength than annealed condition 2. **Refined Grain Structure:** Better toughness and more uniform properties 3. **Stress Relief:** Reduced residual stresses from previous processing 4. **Good Machinability:** Balanced hardness allows efficient machining 5. **Dimensional Stability:** More stable than annealed during machining 6. **Consistent Microstructure:** Uniform properties throughout cross-section 7. **Excellent Base for Hardening:** Ideal condition for subsequent heat treatment 8. **H-Grade Consistency:** Reduced property variation batch-to-batch **Limitations:** 1. **Limited Strength:** Not suitable for high-stress applications without further treatment 2. **Wear Resistance:** Moderate at best; lower than hardened conditions 3. **Not Final Condition:** Typically requires additional processing for final use 4. **Property Variations:** Can occur with different cooling rates in large sections **Special Characteristics:** - **Hardenability Potential:** Excellent base for subsequent quenching and tempering - **Response to Surface Hardening:** Good candidate for induction or flame hardening - **Weldability:** Fair with proper procedures (preheat and post-heat recommended) - **Fatigue Performance:** Adequate for many non-critical applications - **Temperature Stability:** Suitable for service up to 300°C (570°F) **H-Grade Specific Benefits:** - Manufacturing reliability in high-volume production - Reduced scrap and rework rates - Consistent response to all subsequent processing - Supply chain flexibility with multiple qualified suppliers --- ### 9. Applications **Components Used in Normalized Condition:** **Direct Use Applications:** - Machine bases and structural frames - Brackets and mounting components - Linkages and lever arms for moderate loads - Bushings and spacers - General structural components in machinery **Intermediate Processing Applications:** - Gear blanks for subsequent carburizing or through-hardening - Shaft stock for components requiring final heat treatment - Bearing race blanks - Tool holder blanks (for final hardening) - Forging stock for further hot working **Automotive & Transportation:** - Non-critical gears and shafts - Suspension brackets and supports - Engine mounting components - Transmission case components - General hardware and fasteners (to be heat treated) **Industrial Machinery:** - Machine tool components (bases, columns, beds) - Gearbox housings and covers - Pump bodies and housings - Compressor frames and supports - General fabrication components **Construction & Agricultural Equipment:** - Implement frames and structures - Support brackets and mounts - Linkage components for moderate loads - General structural parts **Oil & Gas Industry:** - Valve bodies and bonnets (for final machining and hardening) - Pump housings and cases - Structural components for equipment - General fabrication stock **Typical Service Conditions Suitable for Normalized State:** - Static loads up to 50% of yield strength - Moderate dynamic loads with proper design factors - Ambient to moderately elevated temperatures (-40°C to +300°C) - Non-critical fatigue applications - Lubricated wear conditions **Why Choose H-Grade for These Applications:** - Consistent quality in high-volume production - Predictable manufacturing outcomes - Reduced quality control costs - Improved component reliability - Supply chain consistency --- ### 10. Subsequent Processing Options **Further Heat Treatment from Normalized State:** **Direct Hardening & Tempering:** - **Advantage:** Normalized structure provides uniform starting point - **Procedure:** Re-austenitize at 845-855°C, quench in oil, temper as required - **Result:** More consistent final properties than from as-rolled or annealed **Case Hardening Processes:** - **Carburizing:** Excellent base material due to moderate core hardness - **Carbonitriding:** Good response from normalized condition - **Induction Hardening:** Predictable and consistent results - **Flame Hardening:** Suitable for selective surface hardening **Expected Properties After Subsequent Hardening (Example - 540°C temper):** | Subsequent Treatment | Surface Hardness | Core Hardness | Tensile Strength | Typical Applications | |---------------------|-----------------|---------------|-----------------|---------------------| | **Through-Harden** | 32-38 HRC | 32-38 HRC | 1035-1170 MPa | Gears, shafts | | **Carburize** | 58-63 HRC | 30-38 HRC | 1035-1240 MPa | Wear surfaces | | **Induction Harden** | 55-60 HRC | 25-32 HRC | 860-1035 MPa | Selected areas | **Stress Relieving After Machining:** - **Temperature:** 595-650°C (1100-1200°F) - **Time:** 1-2 hours per inch - **Purpose:** Dimensional stability for precision components - **Benefit:** Reduces machining stresses without affecting normalized structure significantly **H-Grade Advantages in Subsequent Processing:** - Consistent response to heat treatment - Predictable dimensional changes - Uniform case depths in surface hardening - Reduced distortion during final heat treatment - Lower rejection rates in production --- ### 11. Quality Assurance & Testing **H-Grade Specific Testing Requirements:** 1. **Jominy Hardenability Test:** Each heat tested per ASTM A255 2. **Enhanced Chemical Analysis:** Full composition with statistical reporting 3. **Microstructural Examination:** Grain size and uniformity verification 4. **Statistical Property Reporting:** Mean, standard deviation, process capability indices **Standard Testing for Normalized Material:** - **Hardness Testing:** Brinell or Rockwell at multiple locations - **Tensile Testing:** If specified per ASTM A370 - **Chemical Analysis:** Spectrographic verification - **Microstructural Examination:** - Grain size per ASTM E112 - Inclusion rating per ASTM E45 - Microstructure verification - **Dimensional Verification:** Per purchase requirements - **Surface Inspection:** Visual or enhanced methods **Acceptance Criteria:** - **Hardness:** Within specified range (typically 207-255 HB) - **Microstructure:** Uniform fine-grained structure - **Grain Size:** ASTM 6-8 minimum - **Decarburization:** ≤0.25 mm maximum - **Surface Condition:** Free of excessive scale or defects **Certification Requirements:** - **Mill Test Certificate:** EN 10204 3.2 mandatory for H-grade - **Chemical Analysis Certificate:** Full composition report - **Hardenability Test Report:** Jominy curve for each heat - **Mechanical Test Reports:** If specified - **Heat Treatment Records:** Normalizing parameters - **Traceability:** Complete from melt to final product **Special Testing (if specified):** - Ultrasonic testing for internal quality - Magnetic particle inspection for surface defects - Macroscopic examination (sulfur prints, macroetch) - Impact testing at various temperatures - Fatigue testing for critical applications --- ### 12. Storage, Handling & Packaging **Storage Conditions:** - **Environment:** Dry, covered storage recommended - **Temperature:** Ambient conditions acceptable - **Humidity:** <60% relative humidity preferred - **Duration:** 6-12 months without special protection - **Stacking:** Proper support to prevent bending (max 1.5m between supports) **Surface Condition & Protection:** - **As-Normalized:** Typically has light mill scale - **Additional Protection:** Oil or rust preventive may be applied - **Special Finishes:** Pickled and oiled or shot blasted available - **Packaging:** Appropriate for transport and storage conditions - **Identification:** Clear marking of grade, condition, and heat number **Handling Guidelines:** - **Lifting Equipment:** Proper for weight and length - **Transportation:** Secured to prevent damage and movement - **Surface Care:** Avoid impacts that could cause surface damage - **Cleaning:** Scale removal may be required before use **Shelf Life & Maintenance:** - **Indoor Storage:** 12-18 months with basic protection - **Outdoor Storage:** Not recommended without special protection - **Inspection:** Regular checks for corrosion (monthly recommended) - **Re-protection:** As needed based on storage conditions and duration **Packaging Options:** - **Standard:** Bundled with steel straps, ends protected - **Enhanced:** Individual wrapping or VCI paper - **Export:** Heavy-duty waterproof packaging - **Identification:** Tags and stencils for easy identification --- ### 13. Technical Recommendations **Design Guidelines:** - **Allowable Stresses:** Based on normalized properties, not hardened - **Safety Factors:** - Static loading: 2.5-3.0 (based on yield strength) - Fatigue loading: 2.0-2.5 (based on endurance limit) - Impact loading: 3.0-4.0 (consider temperature and notch effects) - Combined loading: 3.0 minimum - **Notch Effects:** Consider in design despite moderate notch sensitivity - **Temperature Limits:** Maximum continuous service ~300°C (570°F) - **Corrosion Protection:** Required for harsh environments **Manufacturing Recommendations:** - **Machining:** Use sharp tools and adequate coolant - **Welding:** Preheat 150-200°C recommended, post-weld heat treat if required - **Forming:** Hot forming preferred for significant deformation - **Finishing:** Consider final heat treatment requirements in planning - **Quality Control:** Establish check points throughout manufacturing **Procurement Specification Example:** ```plaintext MATERIAL: AISI 8650H Alloy Steel CONDITION: Normalized per ASTM A29 HARDNESS: 207-241 HB (for 25-50 mm diameter) CHEMISTRY: Per AISI 8650H requirements including H-grade controls MICROSTRUCTURE: Uniform fine-grained, grain size ASTM 6-8 minimum HARDENABILITY: Must meet SAE J1268 band for 8650H FORM: As required (round, square, flat, etc.) SURFACE: Free of excessive scale, light rust preventive applied CERTIFICATION: EN 10204 3.2 with Jominy test report TESTING: Hardness test each end and middle; microstructure sample TRACEABILITY: Complete from melt to final product ``` **Special Application Notes:** 1. This material is typically an intermediate condition 2. Final heat treatment usually required for service applications 3. H-grade ensures consistent response to subsequent processing 4. Statistical process control recommended for manufacturing **Environmental & Safety:** - **Normalizing Process:** Standard industrial heat treatment - **Machining:** Standard steel machining precautions apply - **Disposal:** Fully recyclable as steel scrap - **Safety Data:** MSDS available from suppliers - **Regulatory Compliance:** Meets standard environmental regulations --- ### 14. Economic & Manufacturing Considerations **Cost Analysis:** - **Material Cost:** 5-10% premium over standard 8650 - **Processing Cost:** Normalizing adds cost but improves properties - **Machining Cost:** Lower than hardened material, higher than annealed - **Quality Cost:** Reduced due to H-grade consistency - **Total Cost:** Often favorable for volume production **Manufacturing Advantages:** - Consistent machining performance - Predictable response to heat treatment - Reduced setup time for new batches - Lower scrap and rework rates - Improved utilization of automated equipment **Value Proposition:** - **For Manufacturers:** Reduced variability improves efficiency - **For Designers:** Predictable properties enable optimization - **For Quality Assurance:** Reduced testing requirements - **For Supply Chain:** Multiple sources provide identical material **Selection Guidelines:** - **Choose Normalized 8650H when:** - Consistent properties are critical - Further heat treatment is planned - Volume production requires reliability - Multiple suppliers must provide identical material - **Consider alternatives when:** - Lowest cost is paramount (choose standard grade) - Maximum machinability needed (choose annealed) - Final properties required immediately (choose pre-hardened) **Life Cycle Considerations:** - **Manufacturing Phase:** Consistent quality reduces costs - **Service Phase:** Reliable performance in final application - **Maintenance:** Predictable wear and failure modes - **End-of-Life:** Fully recyclable with standard steel recycling --- **Disclaimer:** This technical data sheet provides information about AISI 8650H alloy steel in the normalized condition. Properties are typical and may vary based on specific processing parameters, section size, and cooling conditions. This material is often an intermediate condition and may require additional processing for final applications. The H-grade designation ensures consistency but does not eliminate the need for proper processing controls. Always consult with materials engineering professionals for specific application requirements and conduct appropriate testing for critical applications. --- **Document Control** - **Document:** TDS-8650H-NORM - **Revision:** 1.0 - **Date:** March 2024 - **Prepared By:** Materials Engineering Department - **Reviewed By:** Quality Assurance Manager - **Approved By:** Technical Director - **Quality System:** ISO 9001:2015, IATF 16949 Certified - **Special Note:** H-grade material requires specific controls and documentation throughout the supply chain -:- For detailed product information, please contact sales. -: AISI 8650H Steel, normalized Specification Dimensions Size： Diameter 20-1000 mm Length <6370 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 8650H Steel, normalized Properties -:- For detailed product information, please contact sales. -:

Applications of AISI 8650H Steel, normalized -:- For detailed product information, please contact sales. -: Chemical Identifiers AISI 8650H Steel, normalized -:- For detailed product information, please contact sales. -:

Packing of AISI 8650H Steel, normalized -:- 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 2841 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