When it comes to advanced materials designed for high-stress environments, Inconel 718 Sheets stand out due to their exceptional strength, corrosion resistance, and ability to endure extreme temperatures. In this blog, we’ll explore how the composition of Inconel 718, with its unique blend of nickel, chromium, and other alloying elements, contributes to its remarkable properties. The composition ensures that Inconel 718 is not only resistant to oxidation and corrosion but also capable of maintaining its structural integrity at elevated temperatures. When we look at its properties, Inconel 718’s high strength, toughness, and resistance to thermal fatigue make it an ideal choice for aerospace, energy, and marine industries. Inconel 718 Sheets, with their reliable performance in harsh environments, prove to be a trusted material for critical applications where performance and longevity are paramount.
What is Inconel 718 Sheet?
Inconel 718 Sheet is one of the nickel-based superalloy products that are famous for their high strength and good corrosion resistance at elevated temperatures. Designed to be used in harsh environments, this alloy is extensively used in the aerospace, power generation and oil & gas sectors. Its sheet form is especially useful in applications where precision fabrication and structural integrity are needed.
Inconel 718 Composition
The superior performance of Inconel 718 sheet stems from its precisely balanced chemical composition.With 50–55% Nickel providing corrosion resistance and high-temperature strength, and 17–21% Chromium enhancing oxidation resistance, the alloy is constructed for longevity.Iron is the base, with Niobium and Tantalum (4.75–5.5%) adding strength by precipitation hardening. Molybdenum (2.8–3.3%) increases resistance to pitting and crevice corrosion. Minor additions of Titanium and Aluminum increase strength and thermal stability, with minute amounts of Cobalt, Manganese and Silicon optimizing overall performance. This intricate mix enables Inconel 718 to excel in the most demanding environments.
| Element | Composition (%) |
| Nickel (Ni) | 50.0 – 55.0 |
| Chromium (Cr) | 17.0 – 21.0 |
| Iron (Fe) | Balance (typically 17 – 20%) |
| Niobium (Nb) + Tantalum (Ta) | 4.75 – 5.50 |
| Molybdenum (Mo) | 2.80 – 3.30 |
| Titanium (Ti) | 0.65 – 1.15 |
| Aluminum (Al) | 0.20 – 0.80 |
| Cobalt (Co) | ≤ 1.0 |
| Manganese (Mn) | ≤ 0.35 |
| Silicon (Si) | ≤ 0.35 |
| Copper (Cu) | ≤ 0.30 |
| Carbon (C) | ≤ 0.08 |
| Phosphorus (P) | ≤ 0.015 |
| Sulfur (S) | ≤ 0.015 |
| Boron (B) | ≤ 0.006 |
Inconel 718 Properties
- High Strength: Inconel 718 maintains higher mechanical strength even at harsh conditions. It maintains structural integrity at high pressure and temperatures.
- This makes it suitable for aerospace and high performance applications.
- Corrosion Resistance: The alloy resists oxidation and corrosion in harsh environments. It works well in acidic, marine and high temperature environments. Such hardness provides extended service life for parts.
- Creep Resistance: Inconel 718 can withstand deformation from long-term mechanical stress. It retains its form and strength under high temperatures in the long term. This is why it can be used for parts under constant load.
- Weldability: It is simple to weld without cracking compared to most other superalloys. It accomodates numerous welding processes with little post-processing.This facilitates easier manufacture and repair assemblies.
- Thermal Stability: The alloy is stable to 1300°F (700°C) without loss of performance. It maintains mechanical and corrosion resistant characteristics at elevated heat. Ideal for turbine engines and exhaust systems.
- Cryogenic Capabilities: Inconel 718 is strong and ductile at very low temperatures. It avoids brittleness, and is good for cryogenic use. Commonly used in aerospace and liquefied gas applications.
These characteristics render it a widely used option across sectors like aerospace (for turbine components and jet engines), marine, chemical processing and nuclear reactors.
Conclusion
Whether you are operating in aerospace, energy or industrial production, Inconel 718 Sheet is an impressive material solution that combines durability, corrosion resistance and high performance in demanding applications. By understanding the composition and properties of 718 Inconel Sheet assists in making intelligent material decisions for durable and reliable engineering outcomes.