Why is the temperature range of Inconel 718 alloy sheets a critical purchasing factor?
For purchasing professionals in the aerospace, power generation, oil and gas, and chemical industries, the operating temperature range of Inconel 718 alloy sheets directly impacts the following aspects: structural integrity and safety, creep and fatigue life, oxidation and corrosion resistance, long-term maintenance costs, and compliance with design specifications and standards.
Failure to fully understand the actual operating temperature range when selecting an alloy can lead to premature failure or unnecessary cost overruns.
What is Inconel 718 plate?
Inconel 718 (UNS N07718) is a precipitation-hardened nickel-based superalloy, primarily strengthened by the γʺ (Ni₃Nb) phase. The main advantages of Inconel 718 alloy plate include high strength from cryogenic temperatures to high temperatures, excellent fatigue resistance, good oxidation and corrosion resistance, and superior weldability compared to many other high-temperature alloys.
Inconel 718 Sheet Temperature Range (Authoritative Data)
3.1 Operating Temperature Range
| Condition | Temperature Range |
|---|---|
| Minimum service temperature | –253°C (–423°F) |
| Continuous service temperature | Up to 650°C (1,200°F) |
| Short-term exposure | Up to 700°C (1,290°F) |
| Solution annealing temperature | 940–980°C |
| Aging temperature | 720–620°C (two-step aging) |
3.2 Temperature vs Strength Retention (Typical Values)
| Temperature (°C) | Yield Strength (MPa) | Tensile Strength (MPa) |
|---|---|---|
| Room Temperature | ≥1,000 | 1,250–1,450 |
| 400°C | ~900 | ~1,200 |
| 600°C | ~720 | ~1,050 |
| 650°C | ~650 | ~980 |
| 700°C | Rapid degradation | Not recommended |
4. Oxidation & Environmental Resistance by Temperature
| Temperature Range | Performance |
|---|---|
| ≤600°C | Excellent oxidation resistance |
| 600–650°C | Stable with protective oxide layer |
| >650°C | Oxidation accelerates |
| Sulfur-containing environments | Good resistance |
| Chloride environments | Excellent resistance |
Comparison: Inconel 718 Sheet vs Other Alloys (Temperature Focus)
| Alloy | Max Continuous Temp | Key Difference |
|---|---|---|
| Inconel 718 | ~650°C | Best strength + weldability balance |
| Inconel 625 | ~600°C | Better corrosion, lower strength |
| Inconel X-750 | ~750°C | Higher temp, poorer weldability |
| Haynes 282 | ~800°C | Superior creep, higher cost |
What is the maximum operating temperature of Inconel 718 sheet?
Inconel 718 sheet is a high-strength superalloy used from cryogenic temperatures up to about 1300°F (704°C) for high-strength applications like jet engine parts, maintaining excellent tensile, creep, and rupture strength, but its oxidation resistance extends up to around 1800°F (982°C), with some sources noting use up to 980°C (1800°F) for less demanding strength requirements.
Can Inconel 718 sheet be used above 700°C?
Yes, Inconel 718 sheet can be used up to around 700°C (1300°F) for long-term high-strength applications, but its performance decreases and microstructural changes (like brittle Laves phase formation) occur above this, especially in the 800-900°C range, making it better for short-term exposure or lower strength needs beyond 700°C.
Inconel 718 suppliers
At GNEE, Inconel 718 is available in various forms to meet diverse industrial needs:
Plates and Sheets (cold rolled and hot rolled)
Bars and Rods (round, square, hexagonal)
Tubes (seamless and welded)
Wires and Strips (for springs, fasteners, electrical applications)
Forgings and Custom Parts (according to drawings or specifications)
Specifications: UNS NO7718, WNR 2.4668, AFNOR NC19FeNb, JIS NCF 718, GOST ХН75МБТЮ, EURONORM NiCr22Mo9Nb, OR ЭИ602, BS NA 21.
Temperature Range: -423°F to 1300°F.
Testing and Documentation: Mill Test Certificates, EN 10204 3.1, Chemical Reports, Mechanical Reports, Destructive Testing Reports, Non-Destructive Testing Reports, PMI Test Reports, Visual Inspection Reports, Third-Party Inspection Reports, NABL Certified Laboratory Reports.
Packaging: Wooden crates, bubble wrap, steel strapping, or packaged according to customer requirements.
