Carpenter,Micro-Melt® M-4 Alloy (AISI M4)

Carpenter Micro-Melt® M-4 Alloy (AISI M4) Product Information -:- For detailed product information, please contact sales. -: Carpenter Micro-Melt® M-4 Alloy (AISI M4) Synonyms -:- For detailed product information, please contact sales. -:

Carpenter Micro-Melt® M-4 Alloy (AISI M4) Product Information -:- For detailed product information, please contact sales. -: ## **Carpenter Micro-Melt® M-4 Alloy (AISI M4)** ### **Premium High-Speed Steel for Demanding Cutting Applications** --- ### **Product Overview** Carpenter Micro-Melt® M-4 is an advanced molybdenum-tungsten high-speed steel (HSS) produced via proprietary powder metallurgy technology. As a premium version of standard AISI M4 tool steel, this alloy delivers significantly improved performance characteristics including superior toughness, enhanced grindability, and more consistent heat treatment response. The Micro-Melt process creates an ultra-fine, homogeneous microstructure that eliminates the carbide segregation common in conventionally melted M4, resulting in exceptional performance predictability and reliability in the most demanding applications. --- ### **Key Advantages** - **Superior Toughness**: Excellent impact resistance and fracture toughness compared to conventional M4 - **Enhanced Wear Resistance**: Fine, uniformly distributed carbides provide optimal abrasion resistance - **Improved Grindability**: Reduced grinding time and improved surface finish capability - **Exceptional Red Hardness**: Maintains cutting hardness at elevated temperatures - **Consistent Performance**: Isotropic properties ensure identical behavior in all directions - **Better Dimensional Stability**: Minimal distortion during heat treatment --- ### **Chemical Composition (%)** | Element | Carbon (C) | Tungsten (W) | Molybdenum (Mo) | Chromium (Cr) | Vanadium (V) | Cobalt (Co) | |---------|------------|--------------|-----------------|---------------|--------------|-------------| | **Content** | 1.25-1.40 | 5.25-6.00 | 4.25-5.00 | 3.75-4.50 | 3.75-4.50 | - | *Additional Elements*: Manganese (Mn): 0.15-0.40%, Silicon (Si): 0.20-0.45% *Note: Cobalt-free formulation distinguishes it from M35/M42 grades* --- ### **Physical & Mechanical Properties** #### **Physical Properties** - **Density**: 8.10 g/cm³ (0.292 lb/in³) - **Melting Point**: 1425°C (2600°F) - **Thermal Conductivity**: 23.5 W/m·K at 20°C - **Coefficient of Thermal Expansion**: 10.8 × 10⁻⁶/°C (20-300°C) - **Modulus of Elasticity**: 215 GPa (31.2 × 10⁶ psi) #### **Mechanical Properties (Hardened & Tempered)** - **Typical Hardness**: 63-66 HRC - **Red Hardness**: Maintains 60 HRC at approximately 540°C (1000°F) - **Transverse Rupture Strength**: 3,500-4,000 MPa (508-580 ksi) - **Compressive Strength**: 3,800-4,200 MPa (551-609 ksi) - **Abrasion Resistance**: Superior to M2 and equivalent to T15 in many applications - **Toughness**: Approximately 30% higher than conventional M4 #### **Heat Treatment Parameters** 1. **Annealing**: - Temperature: 870-900°C (1600-1650°F) - Cool slowly to 540°C (1000°F) at 15°C (25°F)/hour - Annealed Hardness: 240-280 HB 2. **Stress Relieving**: 650-675°C (1200-1250°F) 3. **Preheating**: 815°C (1500°F) and 950°C (1750°F) 4. **Austenitizing**: 1190-1230°C (2175-2250°F) 5. **Quenching**: Oil, salt bath, or vacuum/pressurized gas 6. **Tempering**: - Double or triple temper required - Temperature: 540-580°C (1000-1075°F) - Resulting hardness: 63-66 HRC --- ### **International Standards & Cross-References** | Standard System | Designation | Equivalent/Similar Grade | |----------------|-------------|--------------------------| | **Carpenter** | Micro-Melt M-4, CPM M4 | Primary designation | | **AISI** | M4 | Direct equivalent (PM version) | | **UNS** | T11304 | Unified numbering system | | **ISO** | HS6-5-3-8 | ISO 4957 designation | | **European (EN)** | 1.3344 | Similar composition | | **Japanese (JIS)** | SKH54 | Equivalent HSS grade | | **DIN** | S6-5-3 | German standard | --- ### **Typical Applications** #### **1. Cutting Tools** - **High-Performance Drills**: For stainless steels, high-temperature alloys - **End Mills**: In aerospace and die/mold applications - **Gear Cutters**: Hobs and shapers for hard materials - **Broaches**: For internal splines and keyways - **Reamers**: Precision hole finishing tools - **Threading Tools**: Taps and dies for difficult materials #### **2. Forming Tools** - **Cold Work Punches and Dies**: For high-strength materials - **Shear Blades**: For abrasive or hard materials - **Form Rolls**: In metal forming operations - **Slitter Knives**: For difficult-to-cut metals #### **3. Mold & Die Applications** - **Injection Molds**: For abrasive plastics and composites - **Die Casting Cores and Cavities**: Particularly for aluminum - **Extrusion Dies**: For non-ferrous metals #### **4. Special Applications** - **Woodworking Tools**: For engineered wood products - **Knives**: Industrial cutting blades - **Surgical Instruments**: High-wear components --- ### **Performance Characteristics** #### **Compared to Conventional M4** | Property | Micro-Melt M-4 | Conventional M4 | Improvement | |----------|----------------|-----------------|-------------| | **Toughness** | Excellent | Good | +30% | | **Grindability** | Very Good | Fair | +40% grinding rate | | **Wear Resistance** | Excellent | Very Good | +15-20% | | **Distortion Control** | Excellent | Good | +50% stability | | **Service Life** | Extended | Standard | +25-50% | #### **Operating Parameters** - **Cutting Speeds**: 20-30% higher than M2 HSS - **Feed Rates**: Comparable to conventional M4 - **Coolant Requirements**: Standard HSS practices apply - **Regrinding Intervals**: Extended compared to conventional grades --- ### **Machining & Fabrication** #### **In Annealed Condition** - **Machinability**: Fair (approximately 45% of 1% carbon steel) - **Recommended Tools**: Carbide or premium HSS tools - **Cutting Speeds**: 30-40 SFM for turning operations - **Coolant**: Use liberally for best results #### **In Hardened Condition** - **Grinding**: Use aluminum oxide or CBN wheels - **EDM**: Excellent results with proper parameters - **Polishing**: Achieves excellent surface finishes --- ### **Technical Specifications** #### **Quality Standards** - **Micro-Cleanliness**: Superior to ASTM E45 requirements - **Carbide Distribution**: Uniform, fine carbides (1-3 microns) - **Decarburization**: Controlled to specified limits - **Straightness**: Available to precision tolerances #### **Available Forms** - **Bar Stock**: Round, square, flat - **Forgings**: Custom shapes and sizes - **Billets**: For tool and die manufacturing - **Pre-finished Blanks**: Ground and polished surfaces --- ### **Economic Benefits** #### **Cost-Per-Part Advantages** 1. **Longer Tool Life**: Reduced tool change frequency 2. **Higher Productivity**: Increased cutting parameters possible 3. **Reduced Scrap**: Consistent performance minimizes rejects 4. **Lower Regrinding Costs**: Improved grindability reduces maintenance time 5. **Inventory Reduction**: Fewer tools needed for same production volume **Typical ROI**: 3-8 months in high-volume machining operations --- ### **Application Guidelines** #### **Ideal For** - Machining materials over 35 HRC - Interrupted cuts and difficult geometries - Applications requiring both wear resistance and toughness - High-temperature cutting operations - Tools with complex geometries requiring extensive grinding #### **Consider When** - M2 or M35 steels fail prematurely - Tool chipping is a problem with conventional HSS - Grinding costs are significant - Consistent performance is critical #### **Not Recommended For** - Very light finishing cuts - Applications where extreme hardness (>67 HRC) is required - Corrosive environments without protection --- ### **Maintenance & Regrinding** 1. **Regrind Promptly**: Don't use tools beyond their wear limits 2. **Proper Coolant**: Use during grinding to prevent overheating 3. **Wheel Selection**: Medium-hard grade wheels work best 4. **Inspection**: Check for micro-cracks after heavy grinding 5. **Re-coating**: Consider PVD coatings after regrinding --- ### **Conclusion** Carpenter Micro-Melt® M-4 Alloy represents the evolution of high-speed steel technology, combining the excellent wear resistance and red hardness of conventional M4 with significantly improved toughness and manufacturability. The powder metallurgy manufacturing process eliminates the limitations of ingot-cast steel, providing toolmakers and manufacturers with a material that delivers: 1. **Predictable Performance**: Consistent results from tool to tool 2. **Extended Tool Life**: Reduced downtime and tooling costs 3. **Manufacturing Efficiency**: Easier grinding and heat treatment 4. **Versatility**: Suitable for a wide range of demanding applications For applications where conventional high-speed steels reach their performance limits, Micro-Melt M-4 provides the additional margin of safety, productivity, and reliability that modern manufacturing demands. Whether in high-volume production environments, aerospace component manufacturing, or precision mold making, this advanced material offers a compelling combination of properties that translate directly to improved bottom-line results. --- *For specific application recommendations and technical assistance, consult with Carpenter Technology's application engineering team.* -:- For detailed product information, please contact sales. -: Carpenter Micro-Melt® M-4 Alloy (AISI M4) Specification Dimensions Size： Diameter 20-1000 mm Length <6928 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. -: Carpenter Micro-Melt® M-4 Alloy (AISI M4) Properties -:- For detailed product information, please contact sales. -:

Applications of Carpenter Micro-Melt® M-4 Alloy (AISI M4) -:- For detailed product information, please contact sales. -: Chemical Identifiers Carpenter Micro-Melt® M-4 Alloy (AISI M4) -:- For detailed product information, please contact sales. -:

Packing of Carpenter Micro-Melt® M-4 Alloy (AISI M4) -:- 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 Sheet/Plate 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 3399 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