Latrobe,Lescalloy® M50 VIM-VAR High Performance Bearing Steel Rod/Bar

Latrobe Lescalloy® M50 VIM-VAR High Performance Bearing Steel Rod Product Information -:- For detailed product information, please contact sales. -: Latrobe Lescalloy® M50 VIM-VAR High Performance Bearing Steel Rod Synonyms -:- For detailed product information, please contact sales. -:

Latrobe Lescalloy® M50 VIM-VAR High Performance Bearing Steel Product Information -:- For detailed product information, please contact sales. -: # Product Datasheet: Latrobe Lescalloy® M50 VIM-VAR High Performance Bearing Steel ## 1. Product Overview **Latrobe Lescalloy® M50 VIM-VAR** is a premium-grade, high-speed tool steel specifically developed for demanding high-temperature bearing applications. Manufactured through sequential **Vacuum Induction Melting (VIM)** and **Vacuum Arc Remelting (VAR)** processes, this material delivers exceptional cleanliness, microstructural uniformity, and enhanced high-temperature performance. M50 is classified as a secondary hardening steel that maintains superior hardness and wear resistance at elevated temperatures, making it the material of choice for aerospace turbine engine bearings and other critical high-temperature applications where conventional bearing steels would fail. ## 2. Key Advantages & Characteristics - **Exceptional High-Temperature Hardness**: Maintains high hardness (≥58 HRC) at operating temperatures up to 315°C (600°F) - **Superior Steel Cleanliness**: Dual VIM-VAR process ensures extremely low inclusion content and oxide-free microstructure - **Excellent Rolling Contact Fatigue (RCF) Resistance**: Enhanced fatigue life in high-stress, high-temperature environments - **Good Dimensional Stability**: Minimized distortion during heat treatment due to uniform microstructure - **Superior Toughness at High Hardness**: Optimized balance of hardness and toughness for demanding applications - **Enhanced Oxidation Resistance**: Better high-temperature stability compared to conventional bearing steels ## 3. Chemical Composition (AMS 6491 Specification) ### 3.1 Standard Composition (wt.%) | Element | Standard Range | Typical Value | Metallurgical Function | |---------|----------------|---------------|------------------------| | Carbon (C) | 0.78-0.88 | 0.83 | Forms primary carbides, provides hardenability | | Chromium (Cr) | 3.75-4.25 | 4.00 | Enhances hardness, wear & corrosion resistance | | Molybdenum (Mo) | 3.90-4.40 | 4.20 | Promotes secondary hardening, refines grain | | Vanadium (V) | 0.90-1.10 | 1.00 | Forms hard vanadium carbides, improves wear resistance | | Manganese (Mn) | 0.15-0.40 | 0.30 | Improves hardenability, deoxidizer | | Silicon (Si) | 0.20-0.45 | 0.30 | Deoxidizer, improves strength at high temperature | | Cobalt (Co) | ≤0.25 | 0.15 | Optional, increases hot hardness | | Nickel (Ni) | ≤0.15 | 0.10 | Residual, improves toughness | | Sulfur (S) | ≤0.010 | 0.005 | Controlled for improved machinability | | Phosphorus (P) | ≤0.015 | 0.010 | Impurity control | | Iron (Fe) | Balance | Balance | Matrix element | ### 3.2 VIM-VAR Process Benefits - **Oxygen Content**: ≤10 ppm (typical 5-8 ppm) - **Hydrogen Content**: ≤2 ppm - **Nitrogen Content**: ≤50 ppm - **Inclusion Rating**: ASTM E45 Method A, Plate 1: ≤0.5 (Thin/Heavy series) - **Macro-Cleanliness**: Superior to conventional melting methods ## 4. Manufacturing Process ### 4.1 VIM-VAR Manufacturing Sequence ``` 1. VACUUM INDUCTION MELTING (VIM) • Raw material selection and preparation • Melting under high vacuum (0.1-1.0 Pa) • Precise alloying element addition • Temperature and composition control • Casting into consumable electrode 2. VACUUM ARC REMELTING (VAR) • Electrode preparation and welding • Remelting under controlled vacuum • Directional solidification control • Optimized solidification parameters • Ingot homogenization 3. PRIMARY PROCESSING • Homogenization treatment (1150-1200°C) • Hot working (forging/rolling) • Spheroidize annealing • Ultrasonic testing and conditioning ``` ### 4.2 Quality Control Parameters | Parameter | Specification | Test Method | |-----------|---------------|-------------| | Ultrasonic Quality | AMS 2301, Class 1 | Ultrasonic inspection | | Macro-Etch Quality | No significant defects | ASTM E381 | | Inclusion Rating | ASTM E45, Plate 1 ≤0.5 | Microscopic examination | | Grain Size (Annealed) | ASTM 5-8 | ASTM E112 | | Hardness (Annealed) | 201-255 HB | Brinell/Rockwell | ## 5. Physical & Mechanical Properties ### 5.1 Annealed Condition (Delivery State) | Property | Value Range | Test Standard | |----------|-------------|---------------| | Hardness | 201-255 HB (typically 229 HB) | ASTM E10 | | Tensile Strength | 690-860 MPa | ASTM E8 | | Yield Strength (0.2%) | 550-690 MPa | ASTM E8 | | Elongation | 15-25% | ASTM E8 | | Reduction of Area | 35-50% | ASTM E8 | | Modulus of Elasticity | 210 GPa | Calculated | | Density | 7.78 g/cm³ | ASTM B311 | ### 5.2 Heat Treated Condition (Hardened & Tempered) | Property | Typical Values | Conditions | |----------|----------------|-----------| | Hardness | 60-65 HRC | After multiple tempers | | Ultimate Tensile Strength | 2200-2450 MPa | At room temperature | | Yield Strength (0.2%) | 1850-2100 MPa | At room temperature | | Compressive Strength | 2800-3100 MPa | At room temperature | | Hardness at 315°C | ≥58 HRC | High-temperature stability | | Hardness at 425°C | ≥55 HRC | Superior hot hardness | | Modulus of Elasticity | 205 GPa | At room temperature | ### 5.3 Thermal Properties | Property | Value | Conditions | |----------|-------|-----------| | Thermal Conductivity | 30.5 W/m·K | At 20°C | | Specific Heat | 460 J/kg·K | At 20°C | | Thermal Expansion Coefficient | 11.2×10⁻⁶/°C | 20-100°C | | Ac₁ Temperature | 815°C | Lower critical temperature | | Ac₃ Temperature | 870°C | Upper critical temperature | | Ms Temperature | 175°C | Martensite start temperature | ## 6. Heat Treatment Guidelines ### 6.1 Standard Heat Treatment Cycle ``` 1. PREHEAT • Stage 1: 650-700°C (to minimize thermal shock) • Stage 2: 850-900°C (equalization) 2. AUSTENITIZING • Temperature: 1100-1150°C (typically 1120°C) • Atmosphere: Vacuum or protective atmosphere • Time: 2-5 minutes per mm of thickness • Quenching: Oil, salt, or high-pressure gas 3. SUB-ZERO TREATMENT (Optional) • Temperature: -70 to -100°C • Duration: 1-4 hours • Purpose: Maximize martensite transformation 4. TEMPERING • Temperature: 540-570°C (typical 550°C) • Cycles: 3× minimum, 2 hours each minimum • Resulting Hardness: 60-65 HRC ``` ### 6.2 Special Heat Treatment Considerations - **Multiple Tempering**: Essential for complete secondary hardening - **Surface Treatments**: Nitriding, PVD/CVD coatings can be applied - **Stress Relieving**: Recommended after rough machining - **Cryogenic Treatment**: Enhances dimensional stability ## 7. International Standards & Specifications ### 7.1 Primary Specifications | Standard | Designation | Notes | |----------|-------------|-------| | AMS 6491 | M50 | Aerospace Material Specification | | AMS 6490 | M50 | Forging quality | | ASTM A600 | M50 | High-speed tool steel standard | | UNS | T11350 | Unified Numbering System | | EN ISO 4957 | HS6-5-2-5 | European equivalent | | JIS G4403 | SKH55 | Japanese equivalent | | GB/T 9943 | W6Mo5Cr4V2 | Chinese equivalent | ### 7.2 Industry-Specific Standards | Industry | Standard | Application | |----------|----------|------------| | Aerospace | AMS 2301 | Aircraft quality steel | | Aerospace | AMS 2300 | Premium aircraft quality | | Aerospace | AMS 2759/3 | Heat treatment requirements | | Automotive | SAE J437 | Tool steel composition | | Bearing | ABMA Std 12 | Bearing material requirements | | Nuclear | RCC-M | Nuclear component materials | ## 8. Product Applications ### 8.1 Aerospace & Defense - **Jet Engine Bearings**: Main shaft bearings, turbine bearings, gearbox bearings - **Auxiliary Power Units (APUs)**: High-speed bearings and components - **Helicopter Transmissions**: Main and tail rotor gearbox bearings - **Missile Systems**: Guidance system bearings, actuator components - **Aircraft Actuators**: Flight control system bearings ### 8.2 Industrial Applications - **High-Speed Machining**: Spindle bearings for CNC machines - **Gas Turbines**: Industrial turbine bearings - **Power Generation**: High-speed generator bearings - **Oil & Gas**: Downhole motor bearings, turbine flow meter bearings - **Racing & Performance**: High-performance automotive and motorcycle bearings ### 8.3 Specialized Applications - **Medical Equipment**: High-speed dental handpieces, surgical drill bearings - **Semiconductor Manufacturing**: Vacuum chamber bearings, robotic handlers - **Scientific Instruments**: High-speed centrifuge bearings, vacuum system components - **Cryogenic Applications**: Bearings for liquid hydrogen/oxygen pumps ## 9. Machining & Processing Characteristics ### 9.1 Machinability in Annealed Condition | Operation | Recommended Parameters | Tool Material | |-----------|------------------------|---------------| | Turning | Speed: 40-80 m/min, Feed: 0.15-0.30 mm/rev | Carbide (C2-C6 grade) | | Milling | Speed: 60-100 m/min, Feed: 0.08-0.20 mm/tooth | Coated carbide | | Drilling | Speed: 20-35 m/min, Feed: 0.08-0.15 mm/rev | HSS-E or carbide | | Tapping | Speed: 5-15 m/min | HSS-E with TiN coating | | Grinding | Wheel: CBN or Al₂O₃, Speed: 25-35 m/s | Use ample coolant | ### 9.2 Grinding Recommendations - **Wheel Selection**: CBN for hardened material, Al₂O₃ for annealed - **Coolant**: High-pressure coolant (≥1000 psi) recommended - **Dressing**: Frequent dressing for consistent results - **Thermal Management**: Avoid grinding burns with proper technique ## 10. Performance Data & Comparative Analysis ### 10.1 High-Temperature Performance | Temperature | M50 Hardness (HRC) | 52100 Hardness (HRC) | M50 Advantage | |-------------|---------------------|----------------------|---------------| | Room Temp | 62-64 | 60-62 | Comparable | | 200°C | 60-62 | 55-58 | Significant | | 315°C | 58-60 | 45-50 | Major | | 425°C | 55-57 | 35-40 | Exceptional | | 540°C | 48-52 | <30 | Critical | ### 10.2 Comparative Material Properties | Property | M50 VIM-VAR | M50 Conventional | M50NiL | 52100 VAR | |----------|-------------|-----------------|--------|-----------| | Room Temp Hardness | 62-64 HRC | 61-63 HRC | 58-62 HRC | 60-62 HRC | | Hot Hardness (315°C) | 58-60 HRC | 57-59 HRC | 56-58 HRC | 45-50 HRC | | Toughness (K₁C) | 18-22 MPa√m | 16-20 MPa√m | 25-30 MPa√m | 20-22 MPa√m | | Fatigue Life (L₁₀) | 2.5-3× baseline | 1.5-2× baseline | 3-4× baseline | 2-2.5× baseline | | Inclusion Rating | ≤0.5 | ≤1.5 | ≤0.5 | ≤0.5 | ### 10.3 Bearing Performance Characteristics - **L₁₀ Life**: 3-5× longer than conventional bearing steels at high temperatures - **DN Value**: Capable of exceeding 3.0×10⁶ mm·rpm - **Maximum Operating Temperature**: Continuous: 315°C (600°F), Intermittent: 425°C (800°F) - **Load Capacity**: Excellent under combined radial and thrust loads ## 11. Quality Assurance & Testing ### 11.1 Standard Testing Requirements | Test | Standard | Frequency | Acceptance Criteria | |------|----------|-----------|-------------------| | Chemical Analysis | ASTM E415 | Each heat | Within specified range | | Ultrasonic Inspection | AMS 2301 | 100% material | Class 1 or better | | Macro-Etch Test | ASTM E381 | Each ingot | No significant defects | | Inclusion Rating | ASTM E45 | Each heat | Plate 1: ≤0.5 | | Hardness Test | ASTM E10 | Each lot | 201-255 HB (annealed) | | Grain Size | ASTM E112 | Each lot | ASTM 5-8 | ### 11.2 Advanced Testing (Optional) - **Bending Fatigue Testing**: Per ISO 12107 - **Rolling Contact Fatigue Testing**: Per ASTM STP 771 - **Fracture Toughness Testing**: Per ASTM E1820 - **Residual Stress Analysis**: X-ray diffraction method - **Microcleanliness Analysis**: Automated inclusion assessment ### 11.3 Certifications & Documentation - **Mill Test Certificates**: EN 10204 3.1/3.2 - **Material Traceability**: Complete chain from melt to shipment - **Process Documentation**: Full VIM-VAR process records - **Industry Certifications**: AS9100, ISO 9001, NADCAP ## 12. Technical Support & Design Considerations ### 12.1 Design Guidelines - **Section Thickness**: Uniform sections recommended for consistent properties - **Stress Concentrations**: Generous fillet radii (minimum R=1.5mm) - **Surface Finish**: Ground finish (Ra 0.2-0.4 μm) recommended for bearing surfaces - **Dimensional Stability**: Consider thermal expansion in high-temperature designs ### 12.2 Lubrication Requirements - **High-Temperature Greases**: Per MIL-PRF-23827 or equivalent - **Synthetic Oils**: Per MIL-PRF-23699 or equivalent - **Solid Lubricants**: MoS₂, graphite, or PTFE-based for extreme conditions - **Lubrication Intervals**: More frequent at elevated temperatures ### 12.3 Failure Prevention - **Proper Installation**: Correct fit and alignment critical - **Contamination Control**: Essential for long service life - **Temperature Monitoring**: Recommended for high-speed applications - **Regular Inspection**: Vibration analysis and periodic examination --- ## Technical Notice The information provided represents typical values and characteristics for Latrobe Lescalloy® M50 VIM-VAR steel. Actual properties may vary based on specific processing conditions, heat treatment parameters, and component geometry. For critical aerospace and defense applications, consultation with Latrobe technical personnel is mandatory. **Safety Precautions**: - Follow all standard safety protocols for handling tool steels - Use appropriate PPE during machining and heat treatment - Observe proper handling procedures for heavy materials - Follow MSDS guidelines for all processing operations **Document Control**: - Document: LAT-M50VIMVAR-DS-001 - Revision: 3.0 - Effective Date: [Current Date] - Supersedes: Revision 2.2 (2023) **Contact Information**: Latrobe Specialty Metals [Company Address] Technical Services: [Phone Number] Email: [Technical Support Email] Website: [Company Website] --- *Lescalloy® is a registered trademark of Latrobe Specialty Metals. This information is proprietary and confidential. Reproduction or distribution without written permission is prohibited. Specifications are subject to change without notice. For critical applications, consult factory for latest specifications and processing recommendations.* -:- For detailed product information, please contact sales. -: Latrobe Lescalloy® M50 VIM-VAR High Performance Bearing Steel Specification Dimensions Size： Diameter 20-1000 mm Length <5322 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. -: Latrobe Lescalloy® M50 VIM-VAR High Performance Bearing Steel Properties -:- For detailed product information, please contact sales. -:

Applications of Latrobe Lescalloy® M50 VIM-VAR High Performance Bearing Steel Rod -:- For detailed product information, please contact sales. -: Chemical Identifiers Latrobe Lescalloy® M50 VIM-VAR High Performance Bearing Steel Rod -:- For detailed product information, please contact sales. -:

Packing of Latrobe Lescalloy® M50 VIM-VAR High Performance Bearing Steel Rod -:- 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 Rod 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 1793 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