Incoloy 800 Bars are nickel-iron-chromium alloys with good strength and outstanding resistance to oxidation and carburization in high-temperature exposure. Due to its nickel content Incoloy 800 Bars highly are resistant to both chloride stress-corrosion cracking and to embrittlement from precipitation of sigma phase. The general corrosion resistance is outstanding.
Incoloy 800 is mainly used in applications where resistance to creep and rupture is required with temperatures up to 1100 degrees F. The chemical balance allows Incoloy alloy to exhibit outstanding resistance to carburization, oxidation and nitriding atmospheres.
Mechanical properties
Incoloy 800 Bars have high mechanical strength over a broad temperature range. In general, alloy 800 is used for its strength characteristics at service temperatures up to about 1500 degrees F (816 degrees C). For applications requiring high creep or rupture strength, Incoloy alloys 800H and 800HT are used.
Corrosion Resistance
Incoloy alloy 800 Bars, like many austenitic stainless steel, can be sensitized, or made susceptible to intergranular attack in some aggressive media, by exposure to the temperature range of 1000 to 1400 degrees F (540–760 degrees C).
When Incoloy 800 Round Bars are exposed to heat from welding or other operations, care should be taken to avoid sensitization if the material is to be pickled or subjected to other aggressive environments. Sensitization is not a problem in most high-temperature applications.
Forming
Incoloy 800 Bars exhibits good ductility and hence can be formed using conventional methods. Hot forming of Incoloy Alloy 800 Bars is done in the temperature range of 1600 to 2200 degrees F (870 to 1200 degrees C). Heavy forging should be done at temperatures from 1850 degrees F to 2200 degrees F (1010 degrees C to 1200 degrees C). Forming at temperatures between 1200 and 1600 degrees F (650-870 degrees C) can result in cracking of the bars. The rate of cooling following hot forming is not critical with respect to thermal cracking. However, these Incoloy bars are subject to carbide precipitation in the 1000-1400 degrees F (540- 760 degrees C) temperature range and should be cooled rapidly through that range to avoid sensitization. Cold working may be done on the bars using standard tooling.
Applications of Incoloy 800 Bars:
Heat exchangers and process piping;
Carburizing fixtures and retorts;
Furnace components;
Electric range heating-element sheathing;
For ethylene and steam methane reforming furnaces;
Ammonia effluent coolers.
