Failure Properties of Aluminum and Aluminum Alloys under Impact Conditions.

Abstract

Research under this grant was directed to two distinct tasks. First was study of the kinetics of shock-induced phase transitions in solids; second was measurement of precursor amplitudes in aluminum under carefully controlled conditions. Shock-induced stresses were measured in single crystals of KCl with shock waves propagating in <100>, <110>, and <111> directions and in single crystals of BaF2 with propagation in <111> and <100> directions. KCl measurements give clear evidence of the initiation of transformation at the established (fcc-bcc) transformation pressure. Stress-time profiles in BaF2 with <111> orientation have a complex structure which apparently results from interaction between the shear yielding process and phase transformation. Precursor amplitudes in aluminum are uniformly low for 1060-0 commercial aluminum, 5-9's single crystals, and single crystals doped with .01 and 0.1 atomic percent copper. Variation of heat treatment to change precipitate structure affects precursor amplitude as it does static yield stress.

Document Details

Document Type
Technical Report
Publication Date
Jan 01, 1976
Accession Number
ADA021129

Entities

People

  • G. Richard Fowles
  • George E. Duvall

Organizations

  • Washington State University

Tags

DTIC Thesaurus Topics

  • Aluminum
  • Aluminum Alloys
  • Amplitude
  • Crystal Structure
  • Crystals
  • Heat Energy
  • Heat Treatment
  • Measurement
  • Phase Transformations
  • Precursors
  • Shock
  • Shock Waves
  • Single Crystals
  • Transitions

Fields of Study

  • Physics

Readers

  • Combustion Dynamics and Shock Wave Physics.
  • Materials Science and Engineering.