Method for preparing a nickel superalloy part, and the part thus obtained

摘要

A method for preparing a part in nickel-based superalloy is disclosed. The method comprises the following steps:
elaborating a nickel-based superalloy with a composition capable of providing hardening by double precipitation of a gamma′ phase and of a gamma″ or delta phase;atomizing a melt of the superalloy in order to obtain a powder;sifting the powder;introducing the powder into a container;closing and applying vacuum to the container;densifiying the powder and the container in order to obtain an ingot or a billet;hot forming said ingot or said billet;wherein before the densification step, the powder and the container are heated for at least 4 hrs, at a temperature both above 1,140° C. and at least 10° C. less than the solidus temperature of the superalloy, and at a pressure causing densification of less than or equal to 15% of the powder volume.

主权项

1. A method for preparing a part of nickel-based superalloy by powder metallurgy, including the following steps:
elaboration of a nickel-based superalloy with a composition capable of providing hardening by double precipitation of a gamma′ phase and of a gamma″ or delta phase; atomization of a melt of said superalloy in order to obtain a powder; sifting said powder for extracting the particles thereof having a predetermined grain size; introducing the powder into a container to form a powder and container assembly; closing and applying a vacuum to the container; densification of the powder and of the container by pressurizing the powder and container assembly in order to obtain one of an ingot or a billet; hot forming said ingot or said billet; wherein before the step for densifying the powder and the container, a heat treatment step is performed for at least 4 hours, at a pressure causing densification of the powder of less than or equal to 15% of the initial volume, this treatment taking place under an inert and non-reactive atmosphere at a temperature both above 1,140° C. and at least 10° C. less than the solidus temperature of the superalloy.