The Strengthening of Hexagonal Close-Packed Materials Due to the Presence of Grain Boundaries.

Abstract

The grain size, temperature and strain rate dependences of the stress-strain behavior of polycrystalline hcp metals are analyzed on the basis of a combined Hall-Petch and thermal activation strain rate analyses. The polycrystal parameters are related to single crystal resolved stresses and it is shown that the temperature dependence of Hall-Petch slope k sub epsilon is responsible for the grain size dependence of the strain rate sensitivity and ductile-brittle transition. The flow and fracture behavior of polycrystalline zinc and titanium at 4.2K provided an interesting comparison of the near-brittle failure of zinc as compared with the near-ductile fracture of titanium.

Document Details

Document Type
Technical Report
Publication Date
Jan 01, 1975
Accession Number
ADA009938

Entities

People

  • N. M. Madhava
  • R. W. Armstrong
  • Y. V. R. K. Prasad

Organizations

  • University of Maryland

Tags

DTIC Thesaurus Topics

  • Boundaries
  • Crystal Structure
  • Crystals
  • Ductile Brittle Transition
  • Grain Boundaries
  • Grain Size
  • Materials
  • Metals
  • Polycrystals
  • Single Crystals
  • Strain Rate
  • Titanium
  • Transitions

Readers

  • Materials Science (Mechanical Engineering).
  • Materials Science and Engineering.