Effect of pre-straining on the size effect in molybdenum pillars

  • Author:

    A.S. Schneider, B.G. Clark,
    C. P. Frick, P.A. Gruber, E. Arzt

  • Source:

    Philosophical Magazine Letters, Band 90, Seiten 841-849 (2010)

  • The effect of prior deformation on the mechanical behavior as a function of size is investigated for body-centered cubic (bcc) molybdenum (Mo) pillars. Experiments were performed using focus ion beam (FIB) manufactured [0 0 1] and [2 3 5] Mo micro/nanopillars, which were compressed, re-FIB machined, and compressed again. Unlike bulk materials, pre-straining has a negligible effect on stress?strain behavior of the pillars, suggesting that dislocation storage does not occur in small-scale bcc specimens. The prevailing mechanism behind the size effect is attributed to dislocation nucleation mechanisms.