Alloy 907 UNS N19907: An Overview

In the demanding world of high-performance engineering, materials that can withstand extreme conditions are paramount. Alloy 907 UNS N19907 stands out as a premier iron-nickel-cobalt superalloy engineered for exceptional low thermal expansion and high strength. This unique combination makes it a critical material in aerospace, cryogenic, and precision instrumentation applications where dimensional stability under thermal stress is non-negotiable.

Key Material Properties and Characteristics

The defining feature of Alloy 907 is its controlled thermal expansion coefficient, which remains remarkably low over a wide temperature range from cryogenic levels up to about 400°C. This is paired with high tensile and yield strength, excellent fatigue resistance, and good weldability. Its composition, primarily iron-nickel-cobalt with additions of niobium and titanium, allows it to maintain structural integrity where other metals would warp or fail, ensuring long-term reliability in critical assemblies.

Primary Industrial Applications

This superalloy’s properties directly translate into vital uses. In the aerospace and defense sectors, it is essential for manufacturing seal rings, structural supports, and components in jet engines and airframes that experience significant thermal cycling. For cryogenic systems, such as those in LNG storage and superconducting magnets, Alloy 907 provides stable containment. Furthermore, its use in precision measurement devices and optical platforms highlights its role in technology requiring absolute dimensional accuracy.

Technical Specifications and Data

Understanding the technical data is crucial for engineers and specifiers. Alloy 907 UNS N19907 typically exhibits an ultimate tensile strength exceeding 1100 MPa and a yield strength over 960 MPa at room temperature. Its low coefficient of thermal expansion, approximately 6.0 x 10^-6/°C from 20°C to 200°C, is a key performance metric. The alloy is available in various forms, including bar, wire, sheet, and plate, and can be machined and formed using standard methods for high-strength alloys, followed by appropriate aging heat treatments to achieve optimal properties.

Frequently Asked Questions (FAQ)

What is the main advantage of Alloy 907 over other superalloys?
Its primary advantage is the synergistic combination of very low thermal expansion and high strength, which is uncommon in many materials. This makes it uniquely suited for applications demanding dimensional stability under load across temperature extremes.

Can Alloy 907 be welded easily?
Yes, it exhibits good weldability using common techniques like gas tungsten arc welding (GTAW). However, post-weld heat treatment is often required to restore optimal properties and relieve stresses in the heat-affected zone.

Is Alloy 907 corrosion resistant?
While it offers reasonable resistance to oxidation and some corrosive environments, its primary design focus is mechanical and thermal performance. For applications involving severe corrosion, additional protective coatings or environmental controls may be necessary.

Ready to Specify This Advanced Material?

For your next project that demands unmatched thermal stability and strength, Alloy 907 UNS N19907 could be the ideal solution. To explore detailed datasheets, availability in specific forms, or to discuss your application requirements with experts, we encourage you to contact