August 2022

Journal

On the effect of elemental partitioning to secondary phases after solution and aging heat treatments in a Co-Ni-based superalloy

By:
Costa, A; Oliveira, J; Escobar, Julian; Salvador, C.A.F.; Monteiro, M; Poplawsky, Jonathan D; Nunes, C; Ramirez, Antonio; Tschiptschin, André
Journal Name:
Materials Letters
Page Number:
131377
Volume:
309
Issue Number:
N/A
Publication Date:
August 26, 2022
View DOI Listing:
https://doi.org/10.1016/j.matlet.2021.131377

Abstract

This paper presents the phase stability and elemental partitioning in a Co-40Ni-10Al-7.5W-10Cr-3Nb-0.06B-0.6C (at.%) superalloy (referred to as 3Nb) after a two-step heat treatment. The resulting microstructure consisted of γ, γ′, MC carbides and µ-Co7W6 phase decorating the regions near and at the grain boundaries. Nb preferentially partitioned to the γ′-phase and other elements such as Ni, Cr and W were responsible for the μ-phase formation.