INCONEL® 718
High-Temp Weldable INCONEL® 718 Bar Nickel Alloy
INCONEL® 718 round bar is in stock in the “Solution and Precipitation Heat-Treated” Condition, and ready to ship from Leading Edge Metals & Alloys. We currently offer 3–6 inch diameter bar produced to AMS 5663, with material also covered under ASTM B637 / ASME SB-637 specifications, suitable for demanding high-temperature and high-stress environments where strength, corrosion resistance, and long-term stability are critical.
This superalloy is a precipitation-hardenable nickel-chromium alloy known for its exceptional mechanical strength up to approximately 1300°F (704°C) and excellent resistance to oxidation, corrosion, fatigue, and creep. Compared to many other nickel-based superalloys, INCONEL® 718 offers good weldability and fabrication characteristics, making it a preferred choice for complex, safety-critical components.
Its combination of strength, corrosion resistance, and fabricability makes it a go-to alloy for both OEM production and replacement parts. Widely used across industries that demand reliable performance under extreme conditions, Inconel 718 is commonly used in applications including Aerospace (turbine discs, engine components, and structural fasteners), Defense (missile hardware and propulsion system components), Chemical Processing (high-temperature reactor components, pressure vessels, and fittings), and Energy (downhole tools, valves and mandrels, high-pressure, and high-temperature service components.)
What you need to know about buying INCONEL® 718 Bar
- When sourcing INCONEL® 718 bar, availability, documentation, and material integrity matter. We offer:
- 3–6 inch round bar in stock in the Solution and Precipitation Heat Treated Condition
- Ready-to-ship inventory
- Clear specification alignment (ASM 5663 and ASTM B637)
- Any special tolerance specifications for the OD or Cut to Lengths
- Any special surface condition specifications
- Responsive support from a team experienced in exotic and refractory metals
- If you need additional sizes, cut-to-length options, or downstream machining support, we’ll collaborate with you to assess feasibility and timelines. INCONEL® 718 is machinable but not forgiving. Buyers should expect:
- Higher cutting forces than carbon or stainless steels
- Tool wear if machining parameters are not optimized
- Benefits from rigid setups and controlled feed rates
- The upside: once machined and heat-treated correctly, parts deliver exceptional in-service reliability, which is why the alloy remains so widely specified despite its machining challenges.
Product Selection and Purchasing Options
Beyond Inconel, Leading Edge offers a wide range of products in multiple shapes and sizes, even in small quantities. Many are available for immediate shipment from our warehouse. If we don’t have the specialty material you need, there’s a good chance we can find it. With our flexible purchasing options, you can ensure materials are available when they’re needed. Purchasing options include blanket orders, just-in-time delivery, and consignment materials.
Industry Standards and Requirements
Industries constantly evolve, driven by a growing demand for scientific and technological advancement. Successful experimentation must ensure material integrity, safety, performance, and compliance with strict environmental and operational regulations.
These standards typically focus on aspects like purity, quality, and durability to guarantee that refractory metals meet the demanding conditions of high-stakes research applications. Because they serve multiple industries and extreme environments, this list includes more than average standards and requirements.
Standards and Requirements:
- ASTM International (American Society of Mechanical Engineers): Standards for materials used in energy applications.
- SAE Aerospace Material Specifications (AMS, formerly known as the Society of Automotive Engineers or SAE)
- ASME BPVC (Boiler and Pressure Vessel Code): Guidelines for materials used in pressure vessels and reactors.
- Department of Defense (DoD) Military Standards or Military Specifications (MIL) on the Defense Logistics Agency (DLA) ASSIST Database
We adhere to quality compliance certification standards and statutory regulations that pertain to our exotic materials, processes, custom machining services, traceability, and other aspects of our in-house expertise. Our materials specialists provide expert counsel on metal selection and inspection to ensure you receive materials that meet or exceed your expectations.
Leading Edge Metals & Alloys Certifications include:
- ISO9001:2015 and AS9100D Registered
- ITAR Registered
- NIST SP 800-171 and CMMC Complian
Our deep understanding of this industry stems from our extensive experience, skilled metallurgy professionals, and a history of successful partnerships with leading national research labs.
Frequently Asked Questions
INCONEL® is a family of high-performance nickel-based superalloys designed to maintain strength, corrosion resistance, and oxidation resistance in extreme environments, especially at high temperatures and under mechanical stress.
Different INCONEL® grades (such as INCONEL® 718) are engineered for specific combinations of strength, weldability, fatigue resistance, and temperature capability.
INCONEL® is primarily composed of nickel, with varying amounts of chromium, iron, and other alloying elements, including niobium, molybdenum, titanium, and aluminum.
The exact composition depends on the grade, but these elements work together to provide:
- High-temperature strength
- Resistance to corrosion and oxidation
- Long-term structural stability
INCONEL® is used in applications where conventional steels and alloys fail, particularly in environments involving high heat, pressure, and corrosive exposure.
Common uses include:
- Aerospace engine and turbine components
- Defense and propulsion hardware
- Chemical processing equipment
- Oil and gas downhole tools and valves
It is typically selected for mission-critical components that require reliability.
Yes. Many INCONEL® alloys, including INCONEL® 718, are weldable. In fact, INCONEL® 718 is known for better weldability than many other nickel-based superalloys, due to its resistance to strain-age cracking. Proper procedures, filler metals, and post-weld heat treatment are critical to achieving optimal results.
Yes, INCONEL® can be welded to carbon steel, but it requires careful procedure control. Key considerations include:
- Use of appropriate nickel-based filler metals
- Managing differences in thermal expansion
- Controlling dilution to avoid brittle weld zones
This type of dissimilar-metal welding is common in industrial and energy applications when done correctly.
Yes, INCONEL® can be welded to stainless steel, and this is a relatively common dissimilar-metal weld. Success depends on:
- Correct filler selection
- Controlling heat input
- Accounting for differences in metallurgy and expansion rates
When properly executed, these welds can perform reliably in high-temperature and corrosive environments.
No. INCONEL® does not rust in the way carbon steel does. Because of its high nickel and chromium content, Inconel forms a protective oxide layer that provides excellent corrosion and oxidation resistance. While no material is completely immune under all conditions, Inconel performs exceptionally well in environments that would rapidly degrade standard steels.
INCONEL® 718 is typically a better choice than INCONEL® 625 when higher mechanical strength and fatigue resistance are required, especially at elevated temperatures.
Key differences:
- Strength: INCONEL® 718 is precipitation-hardened, giving it significantly higher yield and tensile strength than INCONEL® 625.
- Fatigue & creep resistance: 718 performs better under cyclic loading and long-term stress at high temperatures.
- Structural applications: 718 is often preferred for load-bearing components, including turbine parts, fasteners, and engine hardware.
- Temperature range: Both alloys perform well at high temperatures, but 718 is commonly specified where strength must be retained up to approximately 1300°F (704°C).
By contrast, INCONEL® 625 is often selected for superior corrosion resistance and fabricability in chemically aggressive environments where extreme mechanical strength is less critical.
In short:
- Choose INCONEL® 718 for strength-driven, high-stress applications
- Choose INCONEL® 625 for corrosion-driven applications with moderate mechanical demands
