2008/02/13 by M. Zaiser, J. Schwerdtfeger, A. S. Schneider +8 · 1 citation
Materials Science · Physics and Astronomy · #Microstructure and mechanical properties #Nonlocal and gradient elasticity in micro/nano structures #Theoretical and Computational Physics #cond-mat.mtrl-sci
paper · pdf · doi:10.1080/14786430802132522
14 pages, 8 figures, submitted to Phil Mag
arxiv created 2008/02/13 · openalex publication_date 2008/05/17 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/29
Plastic deformation of micron and sub-micron scale specimens is characterized by intermittent sequences of large strain bursts (dislocation avalanches) which are separated by regions of near-elastic loading. In the present investigation we perform a statistical characterization of strain bursts observed in stress-controlled compressive deformation of monocrystalline molybdenum micropillars. We characterize the bursts in terms of the associated elongation increments and peak deformation rates, and demonstrate that these quantities follow power-law distributions that do not depend on specimen orientation or stress rate. We also investigate the statistics of stress increments in between the bursts, which are found to be Weibull distributed and exhibit a characteristic size effect. We discuss our findings in view of observations of deformation bursts in other materials, such as face-centred cubic and hexagonal metals.