Alloy 800HT / Incoloy 800HT is a controlled composition derivative of INCOLOY alloy 800H (UNS N08810) and is used for the same creep resistant applications, however the combined effects of mechanical and thermal processing of the alloy permit higher design stresses to be incorporated than are permitted for the conventional alloy.
INCOLOY 800H is a controlled composition derivative of INCOLOY? alloy 800 (UNS N08800). Applications have extended from petrochemical processing reformer tubing, to bellows and flare tips in refinery service.
INCOLOY 800H is widely used in Power generation, superheater and reheater tubing have also employed the material. Heat treatment retorts, muffles jigs and fixtures have also used this material to great effect.
The combined effects of mechanical and thermal processing of Incoloy Alloy 800HT permit higher design stresses to be incorporated than are permitted for the conventional Alloy 800H.
Both materials remain available, subject to commercial considerations, and certain specifications which restrict the service temperature of some grades of INCOLOY alloy 800H.
To avoid possible stress relaxation grain boundary cracking of N08811 in applications above 1000¡ãF the welded fabrication may be heated 1650¡ãF for about one hour per inch of thickness or 30 minutes minimum then air cooled.
Incoloy 800H is a solution heat treated, carbon controlled version of its parent Alloy 800.
The point to note with the higher carbon version of the Incoloy 800H that the modified alloy comes with improved elevated temperature properties.
The Nickel Alloy 800H is known for its excellent cold forming characteristics.
NAS 800H (NCF 800H, UNS N08810)/NAS 800T (UNS N08811) are nickel-iron-chromium alloys that provide high strength and excellent resistance to oxidation and carburization at high temperatures
High creep strength is attained through control over crystal grains¡ªvia high temperature heat treatment, together with fine control over carbon, titanium, and aluminum content.
ncoloy 800H Forgings have good strength and excellent resistance to oxidation, sulfidation and carburization at elevated temperatures.
Incoloy 800H Forgings are components manufactured from chromium nickel alloy with additions of aluminium, titanium and high carbon content.
Incoloy 800H is an iron-nickel-chromium alloy having the same basic composition as Incoloy 800, with significantly higher creep-rupture strength.
The higher strength results from close control of carbon, aluminum, and titanium contents in conjunction with a high temp anneal.
The 800H modification was to control carbon (0.05 to 0.10%) and grain size to (>ASTM 5) to optimize stress rupture properties.
800H, AT (Incoloy 800) is an austenitic heat resistant alloy designed for high temperature structural applications.
The strength of 800H is achieved by controlled levels of carbon, aluminum and titanium along with a 2100¡ãF minimum anneal to achieve a grain size of ASTM 5 or coarser.
800H is commonly welded using RA82 (ERNiCr-3) bare wire for applications under 1450¡ãF.
RA330-04 (N08334) bare wire offers a closer match of thermal expansion coefficient, and somewhat higher strength.
For maximum strength alloy 617 (ERNiCrCoMo-1) bare wire or 117 (ENiCrCoMo-1) covered electrodes are suggested.
Inconel 800, whose chemistry forms over 50% of nickel is known to be more expensive than the former.
Nickel is a costly commodity, which is why its use in an alloy elevates its cost.
Inconel 800 forms a thick yet stable oxide layer. This thick layer is known to protect the outer surface of the Inconel 800 component from further attack.
This phenomenon is the reason why manufacturers recommend using Inconel 800 for extreme temperature and high pressure applications.
Typical applications of Inconel 800 include the food and beverage industry, in addition to being used for heat treatment components.
Due to its high strength and stiffness properties, Inconel 800 is an alloy that is ideal for demanding applications including the marine engineering, aerospace, and chemical processing industries.
INCOLOY alloy 800 (UNS N08800, W. Nr. 1.4876) is a widely used material for construction of equipment requiring corrosion resistance, heat resistance, strength, and stability for service up to 1500¡ãF (816¡ãC).
Alloy 800 offers general corrosion resistance to many aqueous media and, by virtue of its content of nickel, resists stress corrosion cracking.
At elevated temperatures it offers resistance to oxidation, carburization, and sulfidation along with rupture and creep strength.
