Stress coupling effect on ideal shear strength: tungsten as a case study

journal article in Web of Science

English

Mechanical response of a perfect bcc tungsten crystal to a multiaxial loading was investigated from first principles. The multiaxial stress state consisted of the shear stress and a superimposed compressive triaxial stress with various levels of differential stresses. The studied shear system was 〈111〉{110}. Results obtained within a relatively wide range of the compressive stresses showed that increasing hydrostatic triaxial stress (with zero differential stresses) increased the shear strength almost linearly. On the other hand, triaxial stresses with greater portion of the differential components did not have such a simple effect on the shear strength: We found a certain optimum value of the superimposed triaxial stress yielding the maximum shear strength. Any change (both increase and decrease) in the triaxial stress then reduced the ideal shear strength value.

Ideal shear strength; ab initio calculations; stress coupling

ČERNÝ, M.; ŠESTÁK, P.; POKLUDA, J.

5. 12. 2016

Hindawi

1687-8434

Advances in Materials Science and Engineering

2016

12

United States of America

5317985-1

5317985-5

5

http://dx.doi.org/10.1155/2016/5317985

http://hdl.handle.net/11012/63736