AISI Type M46 Tool Steel (UNS T11346)

AISI Type M46 Tool Steel (UNS T11346) Product Information -:- For detailed product information, please contact sales. -: AISI Type M46 Tool Steel (UNS T11346) Synonyms -:- For detailed product information, please contact sales. -:

AISI Type M46 Tool Steel (UNS T11346) Product Information -:- For detailed product information, please contact sales. -: # **Product Introduction: AISI Type M46 Tool Steel (UNS T11346)** ## **Overview** AISI M46 (UNS T11346) is a **premium cobalt-enriched super high-speed steel** specifically engineered for extreme machining applications requiring exceptional red-hardness and wear resistance. Characterized by its **high vanadium and high carbon content**, M46 represents one of the most wear-resistant commercially available high-speed steels in the molybdenum series. This grade is designed for applications where both extreme abrasion resistance and maintenance of cutting edge integrity at elevated temperatures are paramount, particularly in machining superalloys and hardened materials. ## **1. Chemical Composition (Nominal %)** | Element | Content (%) | Primary Function | |---------|------------|------------------| | **Carbon (C)** | 1.22 - 1.30 | Provides high matrix hardness and abundant carbide formation | | **Tungsten (W)** | 1.40 - 2.10 | Enhances hot hardness through solid solution strengthening | | **Molybdenum (Mo)** | 8.00 - 8.50 | Primary hardening element, improves hardenability and hot strength | | **Chromium (Cr)** | 3.70 - 4.20 | Increases hardenability and provides oxidation resistance | | **Vanadium (V)** | **3.00 - 3.30** | **Critical element** - forms extremely hard MC-type carbides for supreme abrasion resistance | | **Cobalt (Co)** | **7.75 - 8.75** | **Critical element** - dramatically increases red-hardness and tempering resistance | | **Silicon (Si)** | 0.15 - 0.40 | Deoxidizer during steelmaking | | **Manganese (Mn)** | 0.15 - 0.40 | Improves hardenability and acts as deoxidizer | | **Sulfur (S)** | ≤ 0.03 | Residual element (controlled for purity) | | **Phosphorus (P)** | ≤ 0.03 | Residual element (controlled for purity) | | **Iron (Fe)** | Balance | Base metal | **Key Chemistry Note:** M46 features the **highest vanadium content among standard molybdenum HSS grades** (3.0-3.3%), combined with significant cobalt (7.75-8.75%). This unique combination provides outstanding abrasion resistance while maintaining excellent hot hardness. The high carbon content ensures adequate matrix hardness to support the hard vanadium carbides. ## **2. Physical & Mechanical Properties** | Property | Typical Value / Condition | |----------|--------------------------| | **Density** | 8.10 - 8.15 g/cm³ (0.293 lb/in³) | | **Melting Point** | Approximately 1420°C (2590°F) | | **Thermal Conductivity** | ~27 W/m·K at 20°C (relatively low, typical for high-alloy HSS) | | **Coefficient of Thermal Expansion** | 11.3 × 10⁻⁶/K (20-600°C) | | **Modulus of Elasticity** | 200-205 GPa (29.0-29.7 × 10⁶ psi) | | **Annealed Hardness** | 255-285 HB | | **Hardened & Tempered Hardness** | **67-70 HRC** (typically optimized at 68-69 HRC for best performance balance) | | **Red Hardness** | Maintains hardness up to **630°C (1165°F)** - excellent retention at elevated temperatures | | **Abrasion Resistance** | **Exceptional** - among the highest of all commercial HSS grades due to high vanadium carbide volume | | **Toughness** | **Relatively Low** - the high hardness and extensive carbide network reduce impact resistance compared to lower-alloy grades | | **Tempering Temperature Range** | 540-600°C (1000-1110°F), **must be triple-tempered** | | **Grindability** | **Poor** (approximately 30-35% relative to M2) - due to high vanadium carbide content | ## **3. International Standards & Cross-References** | Standard | Designation | |----------|------------| | **UNS** | T11346 | | **AISI/ASTM (USA)** | M46 (ASTM A600) | | **ISO (International)** | **HS 2-9-3-8** (ISO 4957: Tool steels) | | **DIN (Germany)** | **1.3248** | | **JIS (Japan)** | No direct equivalent (closest is SKH59 for M43) | | **GB (China)** | **W2Mo9Cr4V3Co8** (approximate equivalent) | | **AFNOR (France)** | **HS 2-9-3-8** | | **SS (Sweden)** | **2732** | ## **4. Product Applications** ### **Primary Cutting Applications:** - **Premium end mills and drills** for machining highly abrasive materials: nickel-based superalloys (Inconel 718, Waspaloy), titanium alloys, cobalt alloys, and hardened steels (45-55 HRC) - **Specialty cutting tools** for composite materials containing abrasive fibers (carbon fiber, fiberglass) - **Broaches and gear hobs** requiring maximum wear resistance and dimensional stability - **Form tools and thread mills** for production runs where extended tool life is critical - **Single-point lathe tools** for high-speed machining of difficult-to-machine materials ### **Specialized Applications:** - **Cold work tooling** for severe abrasive conditions (punches, dies for powder compaction) - **Wear parts** in highly abrasive industrial environments - **Knives for cutting abrasive non-metallic materials** (reinforced plastics, ceramics) ### **Performance Advantage:** M46 provides **exceptional tool life in abrasive machining applications** - typically 50-100% longer than standard cobalt HSS grades when cutting superalloys. Its balanced high hardness and red-hardness make it particularly suitable for applications involving interrupted cuts on difficult materials. ## **5. Processing & Heat Treatment Guidelines** ### **Forging:** - Heat uniformly to **1060-1150°C (1940-2100°F)** - Forge with careful control; do not forge below **950°C (1740°F)** - Cool slowly in furnace or insulating medium after forging ### **Annealing:** - Heat to **845-870°C (1555-1600°F)**, hold sufficiently, then furnace cool slowly to **540°C (1000°F)** - Expected annealed hardness: 255-285 HB - Spheroidize annealing recommended for optimal machinability ### **Hardening (Critical Process):** 1. **Preheat**: **800-850°C (1470-1560°F)** - ESSENTIAL in two stages (500-600°C then 800-850°C) 2. **Austenitize**: **1170-1190°C (2140-2175°F)** - temperature control is critical (lower than M42/M43) 3. **Soak Time**: 2-5 minutes per inch of thickness (minimum) 4. **Quench**: In salt bath, oil, or vacuum furnace with nitrogen cooling 5. **Cool to 40-50°C (105-120°F)** before tempering ### **Tempering (Critical for M46):** - **Immediate tempering** required after quenching (within 30-60 minutes) - Temperature: **540-560°C (1005-1040°F)** - primary range - **Triple tempering mandatory** (2 hours minimum per cycle) - Cool to room temperature between tempers - Typical hardness after tempering: 68-69 HRC ### **Stress Relieving:** - After rough machining: Heat to 600-650°C (1110-1200°F), hold 2 hours, slow cool ## **6. Machinability & Grindability** | Process | Relative Rating (Compared to M2 = 100%) | Notes | |---------|----------------------------------------|-------| | **Machinability (Annealed)** | 40-45% | Difficult due to high hardness and carbide content | | **Grindability** | **30-35%** | Very difficult - requires specialized wheels and techniques | | **EDM Performance** | Acceptable | Slow cutting rates compared to lower-alloy steels | **Grinding Recommendations:** - Use **CBN (cubic boron nitride) or diamond wheels** for best results - Aluminum oxide wheels require frequent dressing - Light cuts with ample coolant to prevent burning - Consider electrolytic grinding for complex geometries ## **7. Quality Assurance & Standards** - **Microcleanliness**: Typically supplied to ASTM E45 with stringent inclusion control - **Carbide Uniformity**: Controlled to ensure even distribution of vanadium carbides - **Decarburization**: Controlled per AMS 2301 or specific customer requirements - **Ultrasonic Testing**: Standard for critical applications - **Hardness Uniformity**: Typically within ±0.5 HRC point for premium grades ## **8. Comparative Performance Summary** | Property | M46 Relative to M2 | M46 Relative to M42 | |----------|-------------------|---------------------| | **Room Temp Hardness** | +3-4 HRC points | Similar | | **Red Hardness** | +20-25% | Similar to slightly better | | **Abrasion Resistance** | +80-100% | +15-25% | | **Toughness** | -40-50% | -20-30% | | **Grindability** | -65-70% | -30-40% | --- **Disclaimer:** The information provided is for reference purposes. Specific processing parameters and applications should be verified with the material supplier's technical data sheets and qualified metallurgical expertise. Performance characteristics may vary based on manufacturing processes, heat treatment, and application conditions. M46 requires specialized heat treatment facilities and expertise for optimal results. -:- For detailed product information, please contact sales. -: AISI Type M46 Tool Steel (UNS T11346) Specification Dimensions Size： Diameter 20-1000 mm Length <6732 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 Type M46 Tool Steel (UNS T11346) Properties -:- For detailed product information, please contact sales. -:

Applications of AISI Type M46 Tool Steel (UNS T11346) -:- For detailed product information, please contact sales. -: Chemical Identifiers AISI Type M46 Tool Steel (UNS T11346) -:- For detailed product information, please contact sales. -:

Packing of AISI Type M46 Tool Steel (UNS T11346) -:- 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 3203 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