MAR-M-247 Centri-Vac Nickel Cobalt Based Alloy，1

### **Product Introduction: MAR-M 247 Centri-Vac Nickel-Based Superalloy** **Overview** MAR-M 247 is a high-performance, precipitation-hardenable nickel-based superalloy specifically designed for the most demanding high-temperature applications. When produced using the "Centri-Vac" process - combining centrifugal casting with vacuum melting - the alloy achieves exceptional metallurgical quality, directional solidification characteristics, and superior mechanical properties. This alloy is renowned for its outstanding high-temperature strength, excellent creep resistance, and superior thermal fatigue performance, making it ideal for critical rotating components in aerospace and industrial gas turbines operating under extreme conditions. --- #### **Chemical Composition (Typical % by Weight)** | Element | Content (%) | Role & Benefit | |---------|-------------|---------------| | **Nickel (Ni)** | Balance | Austenitic matrix formation | | **Cobalt (Co)** | 9.0 - 11.0 | Solid solution strengthening | | **Chromium (Cr)** | 8.0 - 9.0 | Oxidation and hot corrosion resistance | | **Tungsten (W)** | 9.0 - 10.5 | Solid solution strengthening | | **Aluminum (Al)** | 5.3 - 5.7 | Primary γ' former (Ni₃Al) | | **Titanium (Ti)** | 0.9 - 1.3 | Secondary γ' former (Ni₃Ti) | | **Tantalum (Ta)** | 2.8 - 3.2 | Carbide formation and strengthening | | **Molybdenum (Mo)** | 0.5 - 0.7 | Solid solution strengthening | | **Hafnium (Hf)** | 1.2 - 1.6 | Grain boundary strengthening | | **Carbon (C)** | 0.13 - 0.17 | Carbide formation | | **Boron (B)** | 0.010 - 0.020 | Grain boundary strengthening | | **Zirconium (Zr)** | 0.03 - 0.07 | Creep improvement | *Note: "Centri-Vac" refers to proprietary centrifugal casting and vacuum melting processes.* --- #### **Physical & Mechanical Properties** **Physical Properties:** - Density: 8.55 g/cm³ (0.309 lb/in³) - Melting Range: 1295-1345°C (2363-2453°F) - Thermal Expansion: 12.8 μm/m·°C @ 20-100°C - Thermal Conductivity: 16.8 W/m·K @ 500°C **Mechanical Properties (Heat Treated):** - Tensile Strength: 965 MPa (140 ksi) min - Yield Strength (0.2% Offset): 760 MPa (110 ksi) min - Elongation: 6% min - Creep Rupture Strength: Excellent at 980°C (1800°F) --- #### **International Standards and Specifications** While MAR-M 247 is primarily governed by proprietary specifications, key references include: - **AMS 5392:** Investment castings, vacuum melted (similar specification) - **GE S-400:** General Electric material specification - **Pratt & Whitney CS-4000:** Proprietary specification - **OEM-specific standards:** Major gas turbine manufacturers maintain proprietary specifications --- #### **Product Applications** **Aerospace Applications:** - High-pressure turbine blades - Turbine vanes and nozzles - Turbine rotors and disks - Combustion chamber components **Industrial Applications:** - Industrial gas turbine blades - Power generation turbine components - High-temperature fasteners and hardware - Specialized tooling for high-temperature processing --- #### **Key Advantages** 1. **Exceptional High-Temperature Capability**: Maintains mechanical properties up to 1040°C (1900°F) 2. **Superior Creep Resistance**: Optimal for long-term high-stress applications 3. **Excellent Thermal Fatigue Resistance**: Withstands severe thermal cycling 4. **Outstanding Oxidation Resistance**: Performs well in aggressive environments 5. **Enhanced Microstructural Stability**: Maintains properties during extended high-temperature exposure 6. **Directional Solidification Capability**: Suitable for single crystal applications --- **Conclusion** MAR-M 247 Centri-Vac alloy represents the pinnacle of nickel-based superalloy technology for extreme temperature applications in modern gas turbine engines. Its sophisticated chemistry, featuring optimized levels of refractory elements and enhanced grain boundary strengthening, delivers unparalleled performance for the most demanding rotating components. The Centri-Vac manufacturing process ensures superior metallurgical quality and reliability, making this alloy a preferred choice for critical aerospace and power generation applications where failure is not an option. Governed by stringent OEM specifications and quality standards, MAR-M 247 continues to enable advancements in turbine efficiency and operational reliability.

Packing of Standard Packing: 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 3414 gallon liquid totes Special package is available on request.