Shock compression and spallation of palladium bicrystals with a Σ5 grain boundary

Abstract

We investigate an elementary process of shock response of grain boundaries (GBs) using molecular dynamics simulations: shock compression and spallation in Pd bicrystals with a symmetric Σ5/(210)/〈100〉 GB. The loading direction is normal to GB. An elastic shock may induce the elastic-plastic or two-wave structure at the GB. The GB serves as a wave scattering center for the transverse motion perpendicular to the GB rotation axis and the shock direction: it induces a phase shift of 180∘, an increase in the amplitude of the particle velocity, GB sliding and grain orientation distortion. The GB is the preferred nucleation site both for dislocations and voids. Our results suggest that both microstructure and the loading geometry contribute to dynamic response of a solid.

Document Details

Document Type
Pub Defense Publication
Publication Date
Apr 15, 2011
Source ID
10.1063/1.3572039

Entities

People

  • Bedri Arman
  • Hieu H. Pham
  • S. N. Luo
  • Tahir Çağin

Organizations

  • Los Alamos National Laboratory
  • Office of Naval Research
  • Texas A&M University

Tags

Fields of Study

  • Physics

Readers

  • Combustion Dynamics and Shock Wave Physics.
  • Computer Engineering
  • Materials Science (Mechanical Engineering).