Characteristics of Nicrofer 3220 H - alloy 800 H Nicrofer 3220 H is an austenitic high-strength solid-solution nickel-iron-chromium alloy with controlled levels of carbon, aluminium, titanium, silicon and manganese and controlled content of (Al + Ti).

The analysis is similar to that of Nicrofer 3220, but a special solution anneal treatment (with grain sizes = 90 µm/ASTM No. 4) gives significantly increased creep-rupture strength above 600 °C (1110 °F).

For services below 600 °C (1110 °F) the use of soft annealed Nicrofer 3220 is suggested.

Nicrofer 3220 H is characterized by:

• good creep-rupture properties at temperatures above 600 °C (1110 °F) without loss of ductility during long-term use at temperatures below 700 °C (1290 °F), due to limitation of (Ti + Al) content to max. 0.7 %

• good resistance to reducing, oxidizing and nitriding

atmospheres and to atmospheres which alternate between reducing and oxidizing conditions

• metallurgical stability in long-term application at high temperatures