AUSTENITIC ALLOY WITH HIGH ALUMINUM CONTENT AND ASSOCIATED DESIGN PROCESS

摘要

The invention relates to an austenitic alloy based on nickel, chromium and iron, and with a high aluminum content, intended for use at a given operating temperature (Ts) between 900 ° C and 1200 ° C, the alloy comprising the following compounds in percentages by mass: • chromium between 20% and 32%, • nickel between 30% and 60%, • aluminum between 3.5% and 6%, • carbon between 0.4% and 0.7%, • titanium between 0.05% and 0.3%, • niobium and / or tantalum between 0.6% and 2%, • at least one rare earth between 0.002% and 0.1 %, • silicon between 0 and 0.5%, • manganese between 0 and 0.5%, • tungsten between 0 and 2%, • iron to balance the compounds of the alloy. The alloy exhibits less than 1% by volume of a B2-NiAl intermetallic phase and less than 1% by volume of an alpha prime phase rich in chromium, after the service temperature (Ts) has been applied to it.