First-principles modeling of superlattice intrinsic stacking fault energies in Ni3Al based alloys. (15th February 2018)

• Record Type: Journal Article
• Authors: Breidi, A.; Allen, J.; Mottura, A.
• Is Part Of: Acta materialia. Volume 145(2018)
• Page Start: 97
• Page End: 108
• Publication Date: 2018-02-15
• Subjects: First-principles -- Ni superalloys -- Alloys -- Stacking faults -- Dislocations; Materials -- Periodicals; Materials science -- Periodicals; Materials -- Mechanical properties -- Periodicals; Metallurgy -- Periodicals; Chemistry, Inorganic -- Periodicals; 620.112
• DOI: 10.1016/j.actamat.2017.11.042
• Languages: English
• ISSNs: 1359-6454

Abstract

Abstract: High-throughput quantum mechanics based simulations have been carried out to establish the change in lattice parameter and superlattice intrinsic stacking fault (SISF) formation energies in Ni3 Al-based alloys using the axial Ising model. We had direct access to the variation in SISF energies due to finite compositional change of the added ternary transition metal (TM) element through constructing large supercells, which was equally necessary to account for chemical disorder. We find that most added TM ternaries induce an important quasi-linear increase in the SISF energy as a function of alloying composition x . The most pronounced increase corresponds to Fe addition, while Co addition decreases the SISF energy monotonically. Our results shed light on the role played by TM elements on strengthening L12 Ni3 Al precipitates against stacking fault shear. The data are of high importance for designing new Ni-based superalloys based on computational approaches. Graphical abstract: Image 1