Incoloy 800HT

┃Material

UNS N08811, Alloy 800HT, W.Nr. 1.4959, Incoloy® 800HT

Note that the designation “Incoloy®” is registered trademarks of the Special Metals Corporation group of companies.

┃ Overview

The mechanical properties of UNS N08810 and UNS N08811, combined with their resistance to high temperature corrosion, make these alloys exceptionally useful for many applications involving long-term exposure to elevated temperatures and corrosive atmospheres. Incoloy 800H and Incoloy 800HT have significantly higher creep and rupture strength than Incoloy 800. The base elements in three alloys are the same, only carbon, aluminum and titanium differ slightly. The carbon content of Incoloy 800 is 0.10% max with no limit on the lower end. The carbon content for Incoloy 800H is 0.05 to 0.10%. The carbon content for Incoloy 800HT is further restricted to 0.06–0.10%. In addition to the controlled carbon content, Incoloy 800H and 800HT receive a high-temperature annealing treatment that produces an coarser grain size. The annealing treatment and restricted chemical composition are responsible for these alloys having greater creep and rupture strength.

┃ Chemical Composition (%)

┃ Mechanical Property

┃ Application

In Ethylene Production: Convection and cracking tubes, pigtails

In Hydrocarbon Processing: Catalyst tubing, convection tubing, pigtails, outlet manifolds, and quenching-system piping for steam/hydrocarbon reforming

In Vinyl Chloride Monomer Production:  Cracking tubes, return bends and inlet and outlet flanges

In Oxy-alcohol Production: Tubing in hydrogenation heaters

In Power Generation: Steam superheating tubing

In Heat-treating Furnaces: Radiant tubes, muffles, retorts, and assorted furnace fixtures

In Gas-cooled Nuclear Reactors: High temperature heat exchangers

┃Corrosion Resistance

Incoloy 800, 800H, 800HT contains the same nickel, chromium, and iron contents and generally display similar corrosion resistance. Please note, Because Alloy 800HT, 800H are used for their high-temperature strength, corrosive environments to which these alloys are exposed normally involve high temperature reactions such as oxidation and carburization.

┃ Machining

Incoloy 800H and Incoloy 800HT are readily machined by standard methods. Turning operations can be performed with high metal removal rates, good tool life, and good surface finish using coated carbide tools. Good results have also been obtained with high-speed-steel tools, which are better for interrupted cutting.

┃Welding

Like Incoloy 800HT, Incoloy 800H and 800 have the same good weldability. Both are normally used for applications requiring high creep-rupture strength and should be joined with welding products that have suitable strength characteristics for the intended service temperatures, the optimum welding product choice depends on the specific service temperatures involved and the properties needed in the welded joint. For temperatures up to 1450°F (790°C), INCO-WELD A Electrode is used for shielded-metal-arc welding, and INCONEL Filler Metal 82 is used for gas-shielded welding. For service temperatures over 1450°F (790°C), INCONEL Welding Electrode 117 and INCONEL Filler Metal 617 are recommended.

┃ Product Forms

Ø Bar & Rod

Ø Plate & Sheet

Ø Coil & Strip

Ø Pipe & Tube

Ø Fitting: Flange, Tee, Elbow, Reducer etc.

Ø Forging: Ring, Shaft, Circle, Block etc.

┃ Note

Ronsco is a supplier with more than 27 years of experience in the stainless steel and nickel alloy field, we always adheres to the business phiosophy of "customer-centered", tries its best to meet the requirements of customers and pursues win-win cooperation with customers. Are you looking for metal products one-stop supplier! Contact Us Now! Email: service@ronsteel.com