Inconel 617 View AMS Numbers >
Inconel 617 (UNS N06617/W.Nr. 2.4663a) is a solid-solution, strengthened, nickel-chromium alloy. Known for its use in extreme environments, Inconel 617 exhibits high-temperature strength and oxidation resistance and excellent resistance to a broad range of corrosive environments even at temperatures over 1800°F (980°C). Inconel 617’s unique properties make it ideal for use in components in a broad range of industries, including power generation, nuclear, petrochemical, food processing, aerospace, thermal processing, and chemical industries. Alloy 617 has also been customized to fit the specific purpose of USC boilers.
Alloy 617 has a unique composition specifically designed for harsh high-temperature environments subject to pressures and heat. Its a high nickel and chromium composition makes it resistant to both reducing and oxidizing media. It’s aluminum content, combined with its chromium content, provides oxidation resistance at high temperatures, while its cobalt and molybdenum content impart solid-state strengthening. The alloy’s composition also enables it to withstand many wet, corrosive environments.
At high temperatures, the alloy’s chromium and aluminum content form a thin subsurface zone of oxide particles, which provides the correct diffusion conditions for creating a protective chromium oxide layer on the metal’s surface. This alloy also features excellent resistance to carburization and aqueous corrosion by media, although the alloy is generally used only at high temperatures.
Alloy 617 belongs to the Inconel family of highly versatile nickel-chromium-based superalloys. These alloys are remarkably resistant to oxidation and corrosion and have high-performance capabilities under high temperatures. They also offer a superior combination of toughness and strength for demanding applications or harsh environments subject to pressures and heat.
Nickel Inconel 617 is available in different shapes. Its standard product forms are round, forging stock, extruded section, plate, sheet, strip, pipe, tube, and wire. Alloy 617 can be formed and welded using conventional techniques.
Tech Steel & Materials offers Inconel 617 in 3 sub-type specifications and in multiple shapes/forms:
Uses of Inconel 617
Inconel 617 is used widely in a wide variety of applications, such as steam generator superheaters, re-heater parts, and intermediate heat exchangers in gas-cooled reactors. Additional uses include ducting, combustion cans, and transition liners in aircraft and land-based gas turbines, as well as catalyst-grid supports used in producing nitric acid, heat-treating baskets, and reduction boats in the refining of molybdenum, primarily because of its superior resistance to high-temperature corrosion. Other uses include aircraft gas turbines, where high strength-to-weight ratio is desirable, and oil power plants.
Properties of Inconel Alloy 617
Alloy 617’s offers mechanical properties over a wide range of temperatures. Among the alloy’s most critical characteristics is the strength level it maintains at elevated temperatures without losing corrosion resistance. The alloy’s resistance to high-temperature corrosion increases its strength’s usefulness. The alloy’s thermal expansion is much lower than that of other austenitic alloys, however. This feature reduces stresses from differential expansion when it unites with carbon steels or low alloy steels.
Inconel 617 isn’t hardenable by heat treatment but can be cold worked to various tempers. The alloy displays good metallurgical stability for a material of its strength and exceptionally high levels of creep-rupture strength at temperatures of 1800°F (980°C) and above. Inconel 617 also displays good fabricability. Forming and machining can be done using standard techniques for nickel-based alloys.
Inconel 617 also features excellent weldability. Inconel Filler Metal 617 is used for gas-tungsten-arc and gas-metal-arc welding. The alloy also features good hot formability, but it needs high forces thanks to its inherent strength at high temperatures. Its hot-forming characteristics are similar to Inconel Alloy 625. The hot forming or forging temperature range is 1850° F. to 2200° F (1010/1205ºC). Light working can be done, however, at temperatures as low as 1700° (925ºC).
Alloy 617 requires sharp cutting tools that have positive rake angles to minimize work hardening during machining. The cutting feed and depth of cuts, however, need to be sufficient to prevent burnishing the workpiece’s surface. Cobalt roughers should be used as well. Inspecting tooling frequently maximizes quality when machining Inconel Alloy 617.
Physical Properties of Inconel 617
The physical properties of Alloy 617 are shown in the table below: