B407/B163 NICKEL ALLOY 800/800H/800HT SEAMLESS PIPES/TUBES

Product material

Alloy 800H (UNS N08810) and 800HT (UNS N08811) are dual-certified nickel-iron-chromium materials that can resist oxidation, carburization and other high-temperature corrosion. The chemical composition of these two alloys is the same as that of alloy 800 (UNS N08800), but the carbon content in the two grades is higher-0.05-0.10% in alloy 800H, and 0.06-0.10% in alloy 800HT. Alloy 800HT also contains up to 1.0% aluminum and titanium. In addition to chemical composition restrictions, these two alloys must be subjected to the high-temperature annealing treatment, and the average grain size produced is ASTM 5 or coarser. Restricted chemical composition, coupled with high-temperature annealing treatment, ensure that these materials have higher creep and rupture strength than Alloy 800.

Alloy 800H nickel alloy seamless tube has good creep-rupture properties at temperatures higher than 600°C. Since the maximum content of titanium and aluminum is 0.7%, it is still ductile in long-term use at temperatures below 700°C. After alloy 800 is standard annealed, it is recommended to be used at temperatures below 600°C. Alloy 800H can resist reducing, oxidizing and nitriding atmospheres, as well as atmospheres that alternate between reducing and oxidizing. The alloy 800H nickel alloy seamless tube remains stable during long-term high-temperature work.

Alloy 800HT nickel alloy seamless tube has excellent creep strength at temperatures above 700°C. If the application involves frequent temperature deviations below 1290°F (700°C) or the parts are exposed to temperatures below 1290°F (700°C) for a long time, alloy 800H should be used. The high-temperature resistance of alloy 800HT is equivalent to that of alloy 800H. It also remains stable during long-term high-temperature service.