Inconel 800H / 800HT

UNS N08810 / N08811

800H and 800HT are the high-carbon, controlled-grain-size versions of 800, designed for creep service above 600 °C. The carbon content and the minimum grain size give them substantially better rupture strength than the base grade, which is why they dominate reformer and cracking-furnace tubing.

800HT adds a tighter aluminium-plus-titanium range for even better creep performance. Both resist oxidation, carburisation and nitriding, and remain metallurgically stable in long service.

Properties

• High creep and rupture strength above 600 °C
• Resistance to oxidation, carburisation and nitriding
• Metallurgical stability in long-term high-temperature service
• Good resistance to chloride SCC in aqueous service at moderate temperature

Applications

• Reformer and cracking-furnace tubing
• High-temperature process piping and manifolds
• Heat-treatment equipment
• Nitric acid condensers

Forms supplied

• Pipe, tube and flanges
• Bar, plate, ring and forgings

Standards

ASTM B564, B407 (pipe), B409 (plate), B408 (bar); ASME Section VIII for pressure service