First-principles calculation of twin boundary energy and strength/embrittlement in hexagonal close-packed titanium

We performed first-principles calculations to determine the effects of 14 metallic solutes on twin boundary (TB) energy and strength/embrittlement in Ti alloys, with Ti {1 0 (1) over bar 2} and {1 0 (1) over bar 1} TBs as models. Twin formation energies were calculated to identify the effects of solutes on TB stability. Segregation energy and the associated segregation concentration and solubility energy were examined to identify the existence states of the solutes. The influences of solutes on TB strength were identified through strengthening/embrittling energy and its mechanical and chemical contributions. Tensile tests were performed using the uniaxial-strain loading and the uniaxial-stress loading methods to determine maximum TB strength. (C) 2021 The Authors. Published by Elsevier Ltd.

Automated summary

This study used first-principles calculations and tensile tests to investigate the effects of 14 metallic solutes on twin boundaries in Ti alloys. By calculating twin formation energies and examining segregation energy, the study identified how solutes influence twin boundary strength, ultimately determining maximum TB strength.