Detail publikačního výsledku

The origin of lattice instability in bcc tungsten under triaxial loading

ČERNÝ, M.; ŘEHÁK, P.; POKLUDA, J.

Originální název

The origin of lattice instability in bcc tungsten under triaxial loading

Anglický název

The origin of lattice instability in bcc tungsten under triaxial loading

Druh

Článek WoS

Originální abstrakt

Stability of ideal bcc tungsten crystal under triaxial tensile loading was explored from first principles using an analysis of both elastic and dynamic stability. The triaxial stress state was considered a superposition of axial and biaxial transverse stresses. The region of attainable stresses which was delimited using the computed tensile stress maxima was marginally reduced by occurrence of soft phonons in the crystal lattice. While, under purely hydrostatic tension, the crystal was predicted stable up to 48GPa, greater magnitude of a differential stress reduced the value of a mean (hydrostatic) stress associated with first phonon instabilities to about 35GPa. This value is rather close to that recently determined in experiment. Computed phonon spectra were successfully verified with the help of atomistic models of microscopic lattice deformation.

Anglický abstrakt

Stability of ideal bcc tungsten crystal under triaxial tensile loading was explored from first principles using an analysis of both elastic and dynamic stability. The triaxial stress state was considered a superposition of axial and biaxial transverse stresses. The region of attainable stresses which was delimited using the computed tensile stress maxima was marginally reduced by occurrence of soft phonons in the crystal lattice. While, under purely hydrostatic tension, the crystal was predicted stable up to 48GPa, greater magnitude of a differential stress reduced the value of a mean (hydrostatic) stress associated with first phonon instabilities to about 35GPa. This value is rather close to that recently determined in experiment. Computed phonon spectra were successfully verified with the help of atomistic models of microscopic lattice deformation.

Klíčová slova

theoretical strength; triaxial loading; stress superposition; soft phonons; ab initio calculations

Klíčová slova v angličtině

theoretical strength; triaxial loading; stress superposition; soft phonons; ab initio calculations

Autoři

ČERNÝ, M.; ŘEHÁK, P.; POKLUDA, J.

Rok RIV

2018

Vydáno

12.11.2017

ISSN

1478-6443

Periodikum

PHILOSOPHICAL MAGAZINE

Svazek

97

Číslo

32

Stát

Spojené království Velké Británie a Severního Irska

Strany od

2971

Strany do

2984

Strany počet

14

BibTex

@article{BUT138181,
  author="Miroslav {Černý} and Petr {Řehák} and Jaroslav {Pokluda}",
  title="The origin of lattice instability in bcc tungsten under triaxial loading",
  journal="PHILOSOPHICAL MAGAZINE",
  year="2017",
  volume="97",
  number="32",
  pages="2971--2984",
  doi="10.1080/14786435.2017.1363424",
  issn="1478-6435"
}