A novel simplified model for measuring the twinnability of face-centred-cubic metals. (1st February 2020)

• Record Type: Journal Article
• Authors: Liu, Linghong; He, Mengdong; Li, Jianbo; Peng, Xiaofang; Chen, Hong; Wang, Zhipeng; Fan, Touwen
• Is Part Of: Philosophical magazine letters. Volume 100:Number 2(2020)
• Page Start: 63
• Page End: 73
• Publication Date: 2020-02-01
• Subjects: Twinnability -- Al alloys -- solute atoms -- stacking faults -- first-principles calculations; Condensed matter -- Periodicals; Physics -- Periodicals; Solid state physics -- Periodicals; Physique -- Périodiques; 530.41
• DOI: 10.1080/09500839.2020.1716091
• Languages: English
• ISSNs: 0950-0839

Abstract

ABSTRACT: Twinnability is a unique property describing the ease with which a metal plastically deforms by twinning relative to dislocation-mediated slip. Based on first-principles calculations, a simple and effective model, including two calculational supercells with three typical generalised stacking fault structures, is proposed to measure the twinnability of face-centred-cubic metals. Here, we investigated the interaction of alloying atoms with generalised stacking faults and their impact on the twinnability of aluminium alloys. It is found that the twin propensity of Al alloy increases with the increasing concentration of Sc and Ti, and a small increase with Y, while the addition of Sr, Zn, Sn and Ga exhibits opposite trends. It is predicted that twins will remain stable once they were formed in Al–Sc alloys on account of the small extrinsic stacking fault energy.