Why Alloy 718 is the Go-To Material in Aerospace Applications

In the high-stakes world of aerospace engineering, material selection can mean the difference between mission success and catastrophic failure. Among the many options available today, Alloy 718 (commonly known as Inconel® 718) continues to dominate as the material of choice for critical flight hardware and propulsion systems.

This article explores why Alloy 718 aerospace applications are so widespread, particularly in jet engines, and why NeoNickel is the trusted partner for sourcing aerospace-grade nickel alloys.

Why Aerospace Relies on Superalloys

The demands placed on materials in the aerospace sector are some of the most extreme:

• High mechanical loads at elevated temperatures
• Cyclic thermal stresses during takeoff, cruise, and landing
• Aggressive oxidising environments inside combustion chambers
• Strict weight-to-strength ratios for performance and efficiency
• Need for weldability and manufacturability of complex components

Aerospace superalloys, particularly nickel-based systems like Alloy 718, were engineered to address these unique operational challenges. They outperform conventional steels, titanium alloys, and lightweight composites when sustained strength at temperature is non-negotiable.

What Makes Alloy 718 Ideal for Aerospace?

Alloy 718 aerospace usage is so dominant because of its exceptional mechanical stability, weldability, and corrosion resistance, all tailored to survive the harshest operating environments.

Key attributes include:

• High Tensile and Yield Strength up to 650°C: Alloy 718 maintains outstanding mechanical properties in the temperature regimes typical of turbines, combustors, and exhaust structures.
• Exceptional Fatigue Resistance: Essential for components subject to cyclic stresses, such as rotating engine parts and flight-critical fasteners.
• Creep and Stress Rupture Resistance: The alloy’s precipitation-hardened microstructure (γ′ and γ″ phases) ensures long life under prolonged thermal exposure.
• Superior Corrosion and Oxidation Resistance: The chromium-rich composition forms a passive oxide film, making it suitable for oxidising atmospheres and fuel exposure.
• Outstanding Weldability: Unlike many other high-strength superalloys, Alloy 718 resists post-weld cracking, simplifying fabrication of complex assemblies.
• Cryogenic Capability: Alloy 718 retains ductility and fracture toughness at very low temperatures, making it versatile across various aerospace environments.

Alloy 718 Jet Engines: Proven Performance

The aerospace sector’s reliance on Alloy 718 in jet engines is one of the clearest demonstrations of its capabilities.

Applications include:

• Turbine discs
• Compressor blades
• Shafts and seals
• Casings and afterburner components
• Bolts, fasteners, and flanges
• Fuel and hydraulic system parts

Modern turbine engines, including those for commercial aviation, military fighters, and rocket propulsion systems, use Alloy 718 extensively due to its combined strength, weldability, and long-term durability.

Its mechanical stability across thousands of takeoff-and-landing cycles gives manufacturers and operators confidence in engine life predictions and maintenance intervals - critical factors in aerospace economics.

Aerospace Superalloys: Why Alloy 718 Still Leads

Despite the development of newer nickel alloys like Waspaloy, Rene 41, and Alloy 625, Alloy 718 remains the benchmark for a simple reason: It offers the best cost-to-performance ratio across a wide range of operating conditions.

Advantages over other aerospace superalloys:

• Easier to weld and fabricate
• Lower material and processing costs
• Good availability in bar, plate, sheet, and forgings
• Established pedigree with extensive aerospace approvals (AMS, ASTM, and ISO standards)

Because of this, Alloy 718 is not only specified in legacy platforms but continues to be incorporated into next-generation engines and launch systems.

Partnering with NeoNickel for Aerospace Alloy Supply

When it comes to sourcing aerospace-grade materials, quality and traceability are non-negotiable.

NeoNickel offers:

• Certified Alloy 718 to leading aerospace specifications (AMS 5596, AMS 5662, ASTM B637)
• Full traceability and aerospace-level material certification
• Supply in multiple forms: bar, sheet, plate, wire
• Precision processing and technical consultation
• Global logistics support for fast, reliable delivery

NeoNickel ensures that every kilogram of alloy meets the stringent demands of aerospace engineering. View Our Full Alloy 718 Product Range

When mission success depends on performance at the limits of engineering, Alloy 718 remains the go-to aerospace material. Its proven balance of strength, weldability, oxidation resistance, and affordability continues to underpin some of the most critical technologies in modern flight.

Whether you're designing next-generation propulsion systems or maintaining high-performance fleets, NeoNickel is ready to support your requirements for certified aerospace superalloys.

Contact us today to discuss your project, or request a quote.