An Atom-Probe Tomographic Study of the Compositional Trajectories During gamma(f.c.c.)/gamma-prime(L12) Phase-Separation in a Ni-Al-Cr-Re Superalloy

2019/04/30 by Baik, Sung-Il, Mao, Zugang, Ren, Qingqiang +5
#FOS: Physical sciences #Materials Science (cond-mat.mtrl-sci)

paper · doi:10.48550/arxiv.1904.13035

Abstract

The compositional diffusional-trajectories for a phase separation of gamma(f.c.c.)/gamma-prime(L12) phases are studied in a quaternary Ni-10Al-8.5Cr-2Re alloy, aged at 700 deg.C for 0 to 1024 h, utilizing atom-probe tomography (APT). As the gamma-prime(L12)-precipitates grow, the enrichments of Ni, Cr, and Re and depletion of Al on the gamma(f.c.c.) matrix-side develop as a result of diffusional fluxes crossing the gamma(f.c.c.)/gamma-prime(L12) interface.The experimental (APT) compositional trajectories of the two-phases, gamma(f.c.c.)/gamma-prime(L12), are displayed in a quaternary phase-diagram, employing a tetrahedron, and compared with the Philippe-Voorhees (P-V) coarsening model which includes the off-diagonal terms in the diffusion tensor for the multi-component system.

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