Effect of a heterogeneous distribution of particles on the formation of banded grain structure in wrought Alloy 718

Sébastien Coste (1) , Eric Andrieu (1) , Julitte Huez (1)

1 CIRIMAT - Centre interuniversitaire de recherche et d'ingenierie des matériaux

Alloy 718 is known to be sensitive to interdendritic segregation formed during ingot solidification. The occurrence of banded grain structures under heat treating conditions close to 1000 ° C related to interdendritic segregation is often reported. In order to have a better understanding of this microstructural evolution, an extensive experimental program has been carried out. Consequently, a model taking into account the selective dissolution of δ-phase (Ni3Nb) is proposed. A grain growth simulation by Monte-Carlo method is then used to illustrate the grain structure evolution in a banded particle distribution. By comparing experimental data and computer simulation, the relationship between the Monte-Carlo step and the real time is assessed and the range of parameters when heterogeneous microstructures appear is specified.

Mots clés: Monte-Carlo; Grain growth; Alloy 718; Heterogeneous microstructure

Domaines: Matériaux

Sébastien Coste, Eric Andrieu, Julitte Huez. Effect of a heterogeneous distribution of particles on the formation of banded grain structure in wrought Alloy 718. Materials Science and Engineering: A, 2005, 396 (1-2), pp.92-98. ⟨10.1016/j.msea.2004.12.037⟩. ⟨hal-03601497⟩