Makineni SK, Kumar A, Lenz M, Kontis P, Meiners T, Zenk C, Zaefferer S, Eggeler G, Neumeier S, Spiecker E, Raabe D, Gault B (2018)
Publication Language: English
Publication Type: Journal article, Original article
Publication year: 2018
Pages Range: 362-371
DOI: 10.1016/j.actamat.2018.05.074
We propose here a deformation-induced diffusive phase transformation mechanism occurring during shearing of γ′ ordered phase in a γ/γ′ single crystalline CoNi-based superalloy. Shearing involved the creation and motion of a high density of planar imperfections. Through correlative electron microscopy and atom probe tomography, we captured a superlattice intrinsic stacking fault (SISF) and its associated moving leading partial dislocation (LPD). The structure and composition of these imperfections reveal characteristic chemical – structural contrast. The SISF locally exhibits a D019 ordered structure coherently embedded in the L12 γ′ and enriched in W and Co. Interestingly, the LPD is enriched with Cr and Co, while the adjoining planes ahead of the LPD are enriched with Al. Quantitative analysis of the three-dimensional compositional field in the vicinity of imperfections sheds light onto a new in-plane diffusion mechanism as the LPD moves on specific {111} planes upon application of stress at high temperature.
APA:
Makineni, S.K., Kumar, A., Lenz, M., Kontis, P., Meiners, T., Zenk, C.,... Gault, B. (2018). On the diffusive phase transformation mechanism assisted by extended dislocations during creep of a single crystal CoNi-based superalloy. Acta Materialia, 362-371. https://doi.org/10.1016/j.actamat.2018.05.074
MLA:
Makineni, Surendra Kumar, et al. "On the diffusive phase transformation mechanism assisted by extended dislocations during creep of a single crystal CoNi-based superalloy." Acta Materialia (2018): 362-371.
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