Crucible Steel Seamless tube,CPM® Rex® 76®(HS), AISI M48 High Speed Steel Seamless tube Rex® 76®(HS)

Crucible Steel Seamless tube CPM® Rex® 76®(HS), AISI M48 High Speed Steel Seamless tube Rex® 76®(HS) Product Information -:- For detailed product information, please contact sales. -: Crucible Steel Seamless tube CPM® Rex® 76®(HS), AISI M48 High Speed Steel Seamless tube Rex® 76®(HS) Synonyms -:- For detailed product information, please contact sales. -:

Crucible Steel CPM® Rex® 76®(HS), AISI M48 High Speed Steel Rex® 76®(HS) Product Information -:- For detailed product information, please contact sales. -: # **Technical Datasheet: Crucible Steel CPM® Rex® 76®(HS) (AISI M48-type)** --- ## **1. Product Overview** **Crucible CPM® Rex® 76®(HS)** is an ultra-premium **powder metallurgy (PM), super high-cobalt, ultra-high-speed steel (UHS)** engineered as the pinnacle of hot hardness in the high-speed steel family. While conceptually aligned with **AISI M48-type** chemistry, Rex® 76® represents a proprietary formulation optimized through advanced PM processing to deliver **maximum red-hardness, extreme cutting edge stability, and superior grindability** compared to conventional wrought super high-speed steels. This material is designed for the **most extreme high-temperature machining applications** where conventional cobalt HSS grades (M42, M48) reach their thermal limits. With cobalt content exceeding 10%, it offers **exceptional resistance to thermal softening**, enabling productive machining of modern heat-resistant superalloys, hardened steels, and abrasive composites under aggressive cutting conditions where heat generation is intense. --- ## **2. Key International Standards & Designations** | Country/System | Standard Designation | Equivalent/Closest Specification | | :--- | :--- | :--- | | **USA (Crucible)** | **CPM® Rex® 76®(HS)** | Proprietary PM Super Cobalt UHS | | **USA (AISI/SAE)** | **- -** | Performance exceeds AISI M48 specification | | **USA (ASTM)** | **ASTM A600** | Custom PM Grade | | **ISO** | **ISO 4957:2018** | **HS10-?-?-? / Custom** (Beyond standard range) | | **Europe (EN)** | **- -** | Proprietary composition | | **Common Industry Names** | Ultra-Cobalt HSS, Super Red-Hardness Steel | - | | **Performance Class** | **Ultra-High-Speed Steel (UHS)** | - | **Note:** CPM Rex 76 is a proprietary alloy that occupies the performance tier of AISI M48 but with enhanced consistency and manufacturability from PM processing. It represents the extreme end of commercially available cobalt-bearing high-speed steels. --- ## **3. Chemical Composition (Typical %)** The composition is aggressively balanced to maximize hot hardness through synergistic high cobalt, carbon, and tungsten alloying. | Element | Weight % (Typical) | Metallurgical Function & Rationale | | :--- | :--- | :--- | | **Carbon (C)** | **1.45 - 1.60** | Ultra-high carbon ensures maximum matrix carbon saturation and supports extensive secondary carbide formation during tempering, contributing directly to hot hardness and wear resistance. | | **Tungsten (W)** | **9.50 - 10.50** | Very high tungsten content provides exceptional **solid solution strengthening** and forms thermally stable tungsten-rich carbides, the primary foundation for red-hardness. | | **Molybdenum (Mo)** | 3.20 - 4.20 | Works synergistically with tungsten to enhance hardenability and secondary hardening response while refining grain structure. | | **Chromium (Cr)** | 3.50 - 4.50 | Provides essential hardenability and improves oxidation resistance at elevated temperatures. | | **Vanadium (V)** | 2.80 - 3.40 | Provides critical wear resistance through vanadium carbide (VC) formation. Level is optimized to balance extreme wear needs with practical grindability. | | **Cobalt (Co)** | **10.50 - 11.50** | **The defining performance element.** This ultra-high cobalt content dramatically increases the matrix's **tempering resistance and hot hardness** by raising the alloy's "red-hardness" threshold to its practical maximum for steel-based tools. | | **Silicon (Si), Manganese (Mn)** | < 0.50 | Standard additions. | **Key Microstructural Advantages of PM Processing:** - **Cobalt Homogeneity:** Eliminates cobalt segregation bands common in wrought ultra-high-cobalt steels, ensuring uniform thermal properties. - **Refined Carbide Structure:** Fine, spherical carbides (2-4 µm) resist coarsening at high temperatures and improve grindability. - **Isotropic Thermal Behavior:** Predictable performance in complex tool geometries under thermal cycling. --- ## **4. Physical & Mechanical Properties** ### **4.1 Standard Heat Treatment** * **Annealing:** Heat to 870-900°C (1600-1650°F), slow cool. Annealed hardness: **~290-320 HB**. * **Preheating:** **Critical.** Triple preheat at 550°C, 800°C, and 1000°C is strongly recommended. * **Austenitizing:** **1220-1250°C (2230-2280°F).** Extremely high temperature required for solutionizing. **Precision control (±3°C) is mandatory.** Vacuum furnace required. * **Quenching:** **High-pressure gas quench (6+ bar) or salt bath.** * **Tempering:** **Triple or quadruple tempering is mandatory.** Temper at **550-590°C (1020-1095°F)** for 2+ hours each. **Deep cryogenic treatment (-120°C/-184°F minimum)** is essential. * **Expected Hardness:** **69-71 HRC** (can achieve 70-72 HRC with optimal processing). ### **4.2 Mechanical Properties (Hardened & Tempered)** | Property | Value / Rating (Typical) | Performance Context | | :--- | :--- | :--- | | **Hardness** | **69 - 71 HRC** | **Extreme base hardness** for any HSS, enabling geometrically stable, sharp cutting edges. | | **Hot Hardness (600°C/1112°F)** | **~65-67 HRC** | **Exceptional / Best-in-Class (HSS).** Maintains functional cutting hardness at temperatures where most HSS has softened dramatically. | | **Abrasive Wear Resistance** | **Excellent** | Very good due to high hardness and vanadium content, though optimized for heat resistance over pure abrasion. | | **Transverse Rupture Strength (TRS)** | **2,400 - 3,000 MPa** | **Moderate to Low.** Ultra-high cobalt and carbon reduce toughness; tools must be designed for continuous, stable cuts. | | **Compressive Strength** | **~ 3,600 - 4,200 MPa** | Outstanding, suitable for very high-pressure cutting operations. | | **Thermal Fatigue Resistance** | **Excellent** | Resists cracking from repeated thermal shocks in intermittent cutting better than ceramics or carbide. | | **Grindability** | **Fair to Poor** | Challenging. **CBN grinding is mandatory.** The PM structure provides better grindability than equivalent wrought grades. | ### **4.3 Physical Properties (Approximate)** * Density: ~8.45 g/cm³ * Thermal Conductivity: ~27 W/m·K (Higher than standard HSS due to high Co) * Coefficient of Thermal Expansion: 10.8 x 10⁻⁶/K * Modulus of Elasticity: 225-230 GPa --- ## **5. Typical Product Applications** CPM Rex 76 is reserved for **extreme-condition machining** where thermal loading dictates tool failure. * **Ultra-High-Speed & High-Temperature Cutting:** * **Drills & End Mills:** For **dry, high-speed machining of nickel-based superalloys (Inconel 718, 738, Rene 88DT), cobalt alloys (Haynes 188, Stellite), and hardened steels (58+ HRC).** * **Gear Hobs & Shaper Cutters:** For machining high-strength, heat-resistant aerospace gear materials. * **Broaches & Reamers:** For precision finishing of superalloy components where heat buildup is intense. * **Turning & Milling Inserts:** For operations where HSS geometry is preferred over carbide inserts. * **Specialized Wear Components:** Requiring exceptional hardness retention at sustained temperatures up to 600°C (1110°F). --- ## **6. Processing & Manufacturing Guidelines** * **Machinability (Annealed):** **Extremely Poor.** The annealed material is very hard and abrasive. **EDM is the primary shaping method** for finished tool geometries. * **Grindability:** **Fair to Poor.** **CBN wheels are essential.** Requires rigid, high-precision grinding machines with excellent coolant delivery. Diamond grinding may be used for finishing. * **EDM Machining:** **The preferred manufacturing method.** Provides excellent dimensional control. A post-EDM stress relief temper at 150-180°C is critical. * **Surface Treatments/Coatings:** An **exceptional substrate for advanced PVD coatings (AlTiN, AlCrN, AlTiSiN)**. The extreme and stable base hardness allows coatings to perform optimally under severe thermal loads. --- ## **7. Comparative Performance & Selection Notes** | Criterion | **CPM Rex 76** | **CPM Rex 54/T15** | **Wrought M48** | **Whisker-Reinforced Ceramic** | | :--- | :--- | :--- | :--- | :--- | | **Hot Hardness (600°C)** | **~65-67 HRC** | ~63-65 HRC | ~62-64 HRC | **Hardness retained** | | **Room Temp Hardness** | **69-71 HRC** | 68-70 HRC | 68-70 HRC | 92-94 HRA | | **Toughness** | **Low** | Low | **Very Low** | **Very Low** | | **Thermal Conductivity** | Higher | Moderate | Moderate | Low | | **Grindability** | Fair (PM) | Fair (PM) | **Very Poor** | N/A | | **Optimal Application** | **Maximum HSS Heat Resistance** | High Heat + Wear | Theoretical Max Heat | **Extreme Speed, Continuous Cut** | **When to Choose CPM Rex 76:** 1. Machining **next-generation superalloys** where cutting zone temperatures exceed the capacity of M42/M48-type steels. 2. **Maximum possible cutting speeds with HSS tools** are required for productivity gains. 3. **Dry or near-dry machining** of difficult materials where coolant cannot effectively control tool-tip temperature. 4. It serves as a **high-performance, tough alternative to ceramic** in applications where ceramics suffer from thermal shock or brittleness. **Critical Considerations:** - **Low toughness:** Requires extremely stable machining conditions, rigid tooling, and continuous cuts. - **Very high cost:** Material, heat treatment, and grinding costs are substantial. - **Expert processing required:** Demands state-of-the-art heat treatment and grinding capabilities. --- ## **8. Conclusion** **Crucible CPM® Rex® 76®(HS) represents the absolute frontier of hot hardness in commercially available high-speed steel technology.** It is a **specialist material engineered for a specific extreme condition**: the intense thermal environment generated when pushing productivity limits on the world's most heat-resistant alloys. By combining **ultra-high cobalt content with precision PM manufacturing**, Rex 76 achieves a level of red-hardness that redefines the thermal capabilities of steel cutting tools. Its value proposition is clear: **enable higher machining parameters and extended tool life in high-temperature applications** where other HSS grades fail thermally. This material is not merely an incremental improvement but a **strategic enabler for advanced manufacturing** in aerospace, power generation, and high-performance automotive sectors. For machining engineers facing thermal barriers with conventional tooling, **CPM Rex 76 offers the ultimate HSS solution—providing the closest steel-based approximation to the heat resistance of ceramics while maintaining the toughness and manufacturability advantages of premium tool steel.** --- -:- For detailed product information, please contact sales. -: Crucible Steel CPM® Rex® 76®(HS), AISI M48 High Speed Steel Rex® 76®(HS) Specification Dimensions Size： Diameter 20-1000 mm Length <5237 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. -: Crucible Steel CPM® Rex® 76®(HS), AISI M48 High Speed Steel Rex® 76®(HS) Properties -:- For detailed product information, please contact sales. -:

Applications of Crucible Steel Seamless tube CPM® Rex® 76®(HS), AISI M48 High Speed Steel Seamless tube Rex® 76®(HS) -:- For detailed product information, please contact sales. -: Chemical Identifiers Crucible Steel Seamless tube CPM® Rex® 76®(HS), AISI M48 High Speed Steel Seamless tube Rex® 76®(HS) -:- For detailed product information, please contact sales. -:

Packing of Crucible Steel Seamless tube CPM® Rex® 76®(HS), AISI M48 High Speed Steel Seamless tube Rex® 76®(HS) -:- 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 Seamless tube 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 1708 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