ATI Allegheny Ludlum M2 Tool Steel, UNS T11302

ATI Allegheny Ludlum M2 Tool Steel, UNS T11302 Product Information -:- For detailed product information, please contact sales. -: ATI Allegheny Ludlum M2 Tool Steel, UNS T11302 Synonyms -:- For detailed product information, please contact sales. -:

ATI Allegheny Ludlum M2 Tool Steel, UNS T11302 Product Information -:- For detailed product information, please contact sales. -: # **Product Introduction: ATI Allegheny Ludlum M2 Tool Steel (UNS T11302)** ## **1. Overview** **ATI Allegheny Ludlum M2 Tool Steel** is a high-performance **molybdenum-tungsten high-speed steel (HSS)** that serves as the global benchmark for cutting tool applications requiring exceptional **hot hardness (red hardness), wear resistance, and toughness**. Designated as **UNS T11302** and commonly known as **AISI M2**, this alloy revolutionized metalworking by maintaining cutting hardness at temperatures where conventional tool steels soften dramatically. Characterized by its balanced **tungsten-molybdenum-vanadium-carbon matrix**, M2 delivers superior performance in machining operations involving high speeds, heavy feeds, and abrasive materials. ATI's manufacturing ensures consistent carbide distribution and fine grain structure, making it the most widely used high-speed steel for industrial cutting tools worldwide. ## **2. International Standards & Specifications** M2 is the most recognized and standardized high-speed steel grade across all industrial regions. * **Primary Standard Designations:** * **UNS T11302:** Unified Numbering System designation. * **AISI M2:** American Iron and Steel Institute classification (the universal identifier). * **ASTM A600:** Standard Specification for Tool Steel High Speed. * **Key International Equivalents:** * **DIN 1.3343 / EN ISO 4957 HS6-5-2:** The primary European standard (6% W, 5% Mo, 2% V system). * **JIS G4403 SKH51:** Japanese Industrial Standard. * **GB/T 9943 W6Mo5Cr4V2:** Chinese national standard. * **ISO 4957:** **HS6-5-2**. * **Common Trade Names:** Universally known as **M2 High-Speed Steel**, **HSS M2**, or simply **M2**. ## **3. Chemical Composition (Weight %, per ASTM A600)** The composition is optimized for a balance of hot hardness, wear resistance, and toughness through multiple carbide-forming elements. | Element | Composition Range (%) | Role & Benefit | |---------|----------------------|----------------| | **Carbon (C)** | 0.78 – 0.88 | Critical for forming hard carbides with alloying elements and achieving high martensite hardness. Balanced to avoid excessive brittleness. | | **Tungsten (W)** | 5.50 – 6.75 | **Primary hot hardness element.** Forms stable tungsten carbides that resist coarsening at high temperatures, enabling the steel to retain hardness during high-speed cutting (red hardness). | | **Molybdenum (Mo)** | 4.50 – 5.50 | **Primary hardenability and toughness element.** Provides similar hot hardness benefits as tungsten (at about 1% Mo ≈ 1.6-2% W) but improves toughness and reduces carbide segregation. Makes the steel more responsive to heat treatment. | | **Chromium (Cr)** | 3.75 – 4.50 | Provides hardenability, contributes to wear resistance through carbide formation, and improves oxidation resistance at elevated temperatures. | | **Vanadium (V)** | 1.75 – 2.20 | **Critical for wear resistance.** Forms extremely hard vanadium carbides (VC) that provide exceptional abrasion resistance. Higher vanadium improves wear but reduces grindability. | | **Cobalt (Co)** | 0.25 max (Standard M2) | Typically a residual element in standard M2. Cobalt is added in M35/M42 grades specifically to increase hot hardness. | ## **4. Typical Physical & Mechanical Properties (Properly Heat Treated)** * **Essential Heat Treatment (Complex and Critical):** * **Preheating:** **Mandatory multi-stage:** ~450°C (840°F), then ~850°C (1560°F) to prevent thermal shock. * **Austenitizing:** **1190-1220°C (2175-2230°F).** Extremely precise temperature control is required. Salt baths or vacuum furnaces are standard. * **Quenching:** **Oil quench or salt bath quench.** Some grades can be air quenched in thin sections. * **Tempering:** **Triple tempering is mandatory.** Temper immediately after quenching to ~50-70°C (120-160°F). Typical tempering: **540-570°C (1000-1060°F)** for 2+ hours each cycle. This develops **secondary hardening**, achieving peak hardness. * **Mechanical Properties (Hardened & Triple Tempered):** * **Hardness:** **63 – 66 HRC** (typical achievable range, often specified at 64-65 HRC). * **Hot Hardness (Red Hardness):** **Excellent.** Can retain ~60 HRC at temperatures exceeding **600°C (1112°F)**, enabling high-speed machining. * **Compressive Strength:** Extremely high (>3000 MPa). * **Bending Strength/Transverse Rupture Strength:** Good for its hardness level, but lower than toughness-optimized cold work steels. * **Impact Toughness:** Moderate. The high alloy and carbide content prioritize hardness and wear over impact resistance. * **Wear Resistance:** **Exceptional,** particularly against abrasion, due to the high volume of hard tungsten, molybdenum, and vanadium carbides. * **Key Performance Features:** * **Grindability:** **Poor to Fair.** The hard vanadium carbides are extremely abrasive to grinding wheels. Requires appropriate (aluminum oxide or CBN) wheels and techniques. * **Machinability (Annealed):** **Fair.** More difficult than most tool steels due to high alloy content. * **Physical Properties:** * **Density:** ~8.16 g/cm³ * **Thermal Conductivity:** Low (~20 W/m·K at 20°C). * **Coefficient of Thermal Expansion:** ~11.5 × 10⁻⁶/°C ## **5. Product Application** ATI M2 Tool Steel is the workhorse material for a vast array of metal-cutting tools operating at high speeds and under significant thermal stress. * **Metal Cutting Tools:** * **Drills, taps, reamers, end mills, and milling cutters** for machining steels, cast iron, and non-ferrous alloys. * **Gear hobs, broaches, and shaper cutters.** * **Lathe tool bits and single-point cutting tools.** * **Saw Blades and Cutting Inserts:** * **Hacksaw blades, band saw blades, and hole saws.** * **Indexable inserts** for certain applications (though largely superseded by carbides for most insert use). * **Forming and Shearing Tools:** * **Cold heading dies, punches, and thread rolling dies** for high-volume production. * **Shear blades and slitters** for abrasive materials. * **Woodworking Tools:** High-performance planer blades and router bits. ## **6. Key Features & Advantages** * **Superior Hot Hardness (Red Hardness):** Its defining characteristic. Allows tools to maintain a sharp cutting edge at the high temperatures generated during high-speed machining, where carbon and low-alloy tool steels would fail. * **Exceptional Wear Resistance:** The combination of tungsten, molybdenum, and vanadium carbides provides outstanding resistance to abrasive and adhesive wear, extending tool life. * **Good Combination of Hardness and Toughness:** Offers a better toughness-to-hardness ratio than many other high-speed steels (e.g., M42), making it more resistant to chipping in interrupted cuts. * **Cost-Effective High-Performance:** Provides an excellent balance of performance and cost, making it the most economical choice for a wide range of demanding cutting applications. * **Well-Established Heat Treatment Protocols:** Decades of use have resulted in highly refined and reliable hardening procedures. ## **7. Processing Guidelines** * **Heat Treatment:** **Requires specialized expertise and equipment.** Must be performed in salt baths or vacuum furnaces with precise temperature control. **Triple tempering is non-negotiable.** Inadequate tempering leads to retained austenite and premature failure. * **Machining:** Perform all machining in the soft-annealed condition. Use rigid setups and carbide tooling. * **Grinding:** **The major challenge.** Use soft-grade, aluminum oxide wheels (32A-60H) or CBN wheels. Use light passes, sharp wheels, and ample coolant to avoid grinding burns and cracks. * **Surface Treatment:** Often coated with **PVD (TiN, TiAlN, TiCN)** or **CVD** coatings to further enhance lubricity, wear resistance, and thermal barriers, pushing performance beyond the base material limits. **Summary:** ATI Allegheny Ludlum M2 Tool Steel represents the foundational pillar of high-speed steel technology. Its ingeniously balanced composition of tungsten and molybdenum delivers the quintessential properties required for modern metal cutting: the ability to stay hard when hot, resist wear aggressively, and withstand the rigors of production. While premium cobalt grades (M35, M42) offer higher hot hardness and powder metallurgy (PM) grades offer better grindability and consistency, standard M2 remains the most widely used and economically viable high-speed steel for the majority of industrial cutting tools. It is the material that enabled the productivity leaps of the 20th-century machine shop and continues to be indispensable in today's manufacturing landscape. -:- For detailed product information, please contact sales. -: ATI Allegheny Ludlum M2 Tool Steel, UNS T11302 Specification Dimensions Size： Diameter 20-1000 mm Length <7058 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. -: ATI Allegheny Ludlum M2 Tool Steel, UNS T11302 Properties -:- For detailed product information, please contact sales. -:

Applications of ATI Allegheny Ludlum M2 Tool Steel, UNS T11302 -:- For detailed product information, please contact sales. -: Chemical Identifiers ATI Allegheny Ludlum M2 Tool Steel, UNS T11302 -:- For detailed product information, please contact sales. -:

Packing of ATI Allegheny Ludlum M2 Tool Steel, UNS T11302 -:- 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 3529 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