Inconel® alloy 718 - Heat Resisting Alloy (Ni53/Fe19/Cr19/Nb/Mo/Ti) - Material Information

Inconel® alloy 718 is a high-performance, nickel-based superalloy engineered for extreme environments requiring superior strength and corrosion resistance. This precipitation-hardenable material is renowned for maintaining mechanical integrity at elevated temperatures up to 700 °C, making it indispensable in aerospace, energy, and nuclear systems.

Material Overview

Inconel® 718 has a nominal composition of approximately Ni 53%, Fe 19%, Cr 19%, with additions of Nb, Mo, and Ti. Its exceptional high-temperature strength arises from precipitation of ?? (Ni?(Al,Ti)) and ?? (Ni?Nb) phases within a stable austenitic matrix. Microstructural studies have shown the alloy exhibits a combination of ductile and intergranular fracture modes at temperatures between 650 °C and 700 °C, with creep resistance primarily governed by dislocation climb mechanisms (Sugahara et al., 2022). This fine balance of microstructure and thermal stability enables Inconel 718 to withstand prolonged exposure to oxidative and corrosive environments without significant degradation.

Applications and Advantages

Due to its remarkable creep rupture strength, fatigue resistance, and weldability, Inconel® 718 finds critical use in jet engine turbine disks, rocket motors, pressure vessels, and nuclear reactor components. Studies have demonstrated that controlled aging treatments enhance its resistance to pitting corrosion in chloride-containing environments (Caliari et al., 2014). Additionally, microalloying with Nb and Ti improves high-temperature rupture life and stress resistance (Zaman et al., 2016). These synergistic effects make Inconel® 718 one of the most reliable materials for high-stress, high-heat applications.

Goodfellow Availability

Goodfellow supplies Inconel® alloy 718 in a variety of product forms including foil, powder, and bulk materials, suitable for research, prototyping, and industrial use. High purity grades and custom dimensions can be specified to meet unique application needs. Explore all available formats through the Goodfellow product finder.

Explore Inconel® alloy 718 and other advanced materials in Goodfellow’s online catalogue: Goodfellow product finder.

References

• Sugahara, T., Couto, A. A., Barboza, M. J. R., Piorino Neto, F., Takahashi, R. J., & Reis, D. A. P. (2022). *Creep and mechanical behavior study of Inconel 718 superalloy*. Materials Research, 25, e20210280.
• Caliari, F. R., da Rosa, E. F., da Silva, M. A., & Reis, D. A. P. (2014). *Analysis of pitting corrosion on an Inconel 718 alloy submitted to aging heat treatment*. Tecnologia em Metalurgia, Materiais e Mineração, 11(4), 338–344.
• Zaman, T., Farooque, M., Rizvi, S. A., Salam, I., & Waseem, M. (2016). *Investigation of low stress rupture properties in Inconel-718 superalloy*. IOP Conference Series: Materials Science and Engineering, 146, 012051.