Avalanche statistics and the intermittent-to-smooth transition in microplasticity

G. Sparks, Y. Cui, G. Po, Q. Rizzardi, J. Marian, R. Maaß

Research output: Contribution to journalArticlepeer-review

Abstract

Plastic flow at small scales is generally observed to be intermittent, whereas the stress-strain behavior of bulk crystals is mostly smooth. Here we find that when the external deformation rate of small-scale crystals approaches the speed of the crystallographic slip velocity, an intermittent-to-smooth transition of plastic flow is observed. By defining a rate-dependent intermittency parameter, this phenomenon can be captured with a power law covering 5.5 orders of magnitude for Au and Nb micron-sized single crystals with experiments and via simulations for Nb crystals. Our results indicate that the transition to smooth flow is driven by a gradual truncation of the underlying truncated power law that describes the intermittently evolving system. This is caused by a competition of internal and external rates, which aligns with the well-known transitions from serrated to nonserrated flow in metallic glasses or materials with dynamic strain aging.

Original languageEnglish (US)
Article number080601
JournalPhysical Review Materials
Volume3
Issue number8
DOIs
StatePublished - Aug 22 2019

ASJC Scopus subject areas

  • Materials Science(all)
  • Physics and Astronomy (miscellaneous)

Fingerprint Dive into the research topics of 'Avalanche statistics and the intermittent-to-smooth transition in microplasticity'. Together they form a unique fingerprint.

Cite this