# Alloy 907 UNS N19907: Properties and Applications
## Introduction to Alloy 907 UNS N19907
Alloy 907, also known as UNS N19907, is a nickel-iron-cobalt-based superalloy designed for high-temperature applications. This alloy exhibits excellent mechanical properties and resistance to thermal fatigue, making it a popular choice in various industries.
## Chemical Composition
The unique properties of Alloy 907 stem from its carefully balanced chemical composition:
– Nickel (Ni): 38-42%
– Iron (Fe): 38-42%
– Cobalt (Co): 12-16%
– Titanium (Ti): 1.3-1.8%
– Niobium (Nb): 4.5-5.5%
– Aluminum (Al): 0.6-1.2%
## Mechanical Properties
Alloy 907 offers impressive mechanical characteristics:
– Tensile Strength: 1200-1400 MPa
– Yield Strength: 900-1100 MPa
– Elongation: 10-15%
– Hardness: 35-40 HRC
– Creep Resistance: Excellent at temperatures up to 650°C (1200°F)
## Physical Properties
Key physical properties include:
– Density: 8.19 g/cm³
– Melting Range: 1315-1365°C (2400-2490°F)
– Thermal Expansion Coefficient: 12.5 × 10⁻⁶/°C (20-100°C)
– Thermal Conductivity: 11.7 W/m·K at 100°C
## Key Features and Advantages
Alloy 907 offers several notable advantages:
– Exceptional high-temperature strength
– Good oxidation resistance up to 800°C (1470°F)
– Excellent low-cycle fatigue resistance
– Superior thermal stability
– Good weldability and formability
## Applications of Alloy 907
Due to its unique combination of properties, Alloy 907 finds use in various demanding applications:
### Aerospace Industry
Keyword: Alloy 907 UNS N19907
– Jet engine components
– Turbine blades and discs
– Afterburner parts
– High-temperature fasteners
### Power Generation
– Gas turbine components
– Steam turbine parts
– Nuclear reactor components
### Industrial Applications
– High-temperature fasteners
– Pressure vessels
– Heat exchangers
– Chemical processing equipment
## Fabrication and Processing
Alloy 907 can be processed using standard methods:
– Machining: Requires rigid setups and sharp tools
– Welding: Can be welded using TIG, MIG, and resistance welding
– Heat Treatment: Typically solution treated at 980°C (1800°F) and aged at 720°C (1330°F)
– Forming: Can be hot or cold worked, though hot working is preferred
## Comparison with Other Superalloys
Compared to similar alloys like Inconel 718 and Waspaloy, Alloy 907 offers:
– Better thermal fatigue resistance
– Superior low-cycle fatigue properties
– Comparable strength at intermediate temperatures
– More stable microstructure at high temperatures
## Conclusion
Alloy 907 UNS N19907 is a versatile superalloy that combines excellent mechanical properties with good fabricability. Its unique balance of strength, fatigue resistance, and thermal stability makes it indispensable for critical high-temperature applications across aerospace, power generation, and industrial sectors. As technology advances and operating temperatures increase, the demand for reliable materials like Alloy 907 continues to grow.
