Yield anomaly in L12 Co3AlxW1−x vis-à-vis Ni3Al. (15th March 2017)

• Record Type: Journal Article
• Authors: Vamsi, K.V.; Karthikeyan, S.
• Is Part Of: Scripta materialia. Number 130(2017)
• Page Start: 269
• Page End: 273
• Publication Date: 2017-03-15
• Subjects: Planar fault energy -- Yield anomaly -- Co-base superalloys -- Elastic constants -- First principles calculations; Materials -- Periodicals; Metallurgy -- Periodicals; Metalen; Legeringen; Materiaalkunde; Metals, metalworking and machinery industries; Metals; Electronic journals; 620.11
• DOI: 10.1016/j.scriptamat.2016.11.039
• Languages: English
• ISSNs: 1359-6462

Abstract

Abstract: First principles calculations were performed in Co3 Alx W1−x to estimate fault energies, elastic constants and parameters determining the thermodynamic viability and kinetics of yield anomaly. These parameters predict the occurrence of yield anomaly, but only for a limited range of compositions. The driving force for cross-slip resulting in sessile dislocation configurations and cube slip is lower in Co3 Alx W1−x than Ni3 Al due to the less-pronounced anisotropy between antiphase boundary energies on the cube and octahedral planes. Yield anomaly is expected at higher temperatures in Co3 Alx W1−x because of the higher activation energy resulting from the higher shear modulus. Graphical abstract: