γ′ precipitates with a twin orientation relationship to their hosting grain in a γ-γ′ nickel-based superalloy

Suzanne Vernier (1, 2) , Jean-Michel Franchet (2) , Christian Dumont (3) , Philippe Vennegues (4) , Nathalie Bozzolo (1)

1 CEMEF - Centre de Mise en Forme des Matériaux
2 SNECMA Villaroche [Moissy-Cramayel]
3 Aubert & Duval
4 CRHEA - Centre de recherche sur l'hétéroepitaxie et ses applications

In a polycrystalline γ-γ′ nickel-based superalloy, γ′ precipitates with a close-to-twin orientation relationship to their surrounding matrix (named T-type precipitates) are found in recrystallized grains located near specific unrecrystallized grains (named recovered grains). This type of γ/γ′ interface has not been reported in literature before. Inherited from the ingot conversion process, recovered grains are characterized by a high density of micrometric and close-to-coherent γ′ precipitates. Resulting from the interaction of the recrystallization front with the latter precipitates, the T-type precipitates appear to form onto the recrystallization front. The present paper details the crystallographic characteristics of the T-type precipitates

Mots clés: γ-γ′ nickel-based superalloy; Interphase boundary; Twin boundary; Recrystallization

Domaines: Matériaux

Suzanne Vernier, Jean-Michel Franchet, Christian Dumont, Philippe Vennegues, Nathalie Bozzolo. γ′ precipitates with a twin orientation relationship to their hosting grain in a γ-γ′ nickel-based superalloy. Scripta Materialia, 2018, 153, pp.10-13. ⟨10.1016/j.scriptamat.2018.04.037⟩. ⟨hal-01797496⟩