Crystal plasticity modeling and simulation considering the behavior of the dislocation source of ultrafine-grained metal

Y. Aoyagi, T. Tsuru, T. Shimokawa

Research output: Contribution to journalArticle

32 Citations (Scopus)

Abstract

Ultrafine-grained metals (UFGMs) produced by warm- or cold-rolling under severe plastic deformation have attracted interest as high-strength structural materials. UFGMs with a grain size less than 1 μm exhibits remarkable material and mechanical properties, and a computational model predicting these properties is desired in the field of materials science and engineering. In order to clarify the utility of UFGM numerically, it is important to investigate the size effects of metallic materials that depend on initial grain size. It is assumed that such unusual mechanical properties originate in grain size and the enormous volume fraction of the grain boundary. When grains are of the submicron order, dislocation loops are hardly generated from Frank-Read sources smaller than the grain size. Grain boundaries play an important role in dislocation dynamics. In this study, we develop a crystal plasticity model considering the effect of the grain boundary and dislocation source. In order to predict variation of critical resolved shear stress (CRSS) due to grain boundaries or dislocation sources, information on dislocation source and grain boundary is introduced into a hardening law of crystal plasticity. In addition, FE simulation for FCC polycrystal is used to analyze stress-strain responses such as increased yield stress and yield point drop, from the viewpoint of grain size and dislocation density. We thoroughly investigate the effect of dislocation behavior on the material properties of UFGMs.

Original languageEnglish
Pages (from-to)43-57
Number of pages15
JournalInternational Journal of Plasticity
Volume55
DOIs
Publication statusPublished - 2014 Apr 1

Keywords

  • A. Dislocations
  • A. Grain boundaries
  • B. Crystal plasticity
  • C. Finite elements
  • Ultrafine-grained metal

ASJC Scopus subject areas

  • Materials Science(all)
  • Mechanics of Materials
  • Mechanical Engineering

Fingerprint Dive into the research topics of 'Crystal plasticity modeling and simulation considering the behavior of the dislocation source of ultrafine-grained metal'. Together they form a unique fingerprint.

  • Cite this