STUDY OF THE BORDONI PEAK IN SINGLE-CRYSTAL AND POLYCRYSTALLINE COPPER,

Abstract

The Bordoni peak has been investigated in singlecrystal and polycrystalline copper by measuring the longitudinal ultrasonic absorption at 10, 20 and 50 MHz, in the temperature range 80 to 300K. In the single-crystal sample, the measurements have been made in the three principal directions (111), (100) and (110). The values of the activation energy W and the relaxation frequency f sub 0, calculated from the frequency-dependence of the peak on the temperature scale, show a high degree of anisotropy. The comparison of the shape of the peak with Zener's single relaxation theory shows that the peak in the (111) direction is due to a single relaxation process. In the polycrystalline sample and in the other two directions of the single-crystal specimen, the results favour a spectrum of different relaxation frequencies with a constant activation energy. The spectrum width factor gamma differs from one case to the other, but gamma W has approximately the same value which equals the energy obtained in the (111) direction. (Author)

Document Details

Document Type
Technical Report
Publication Date
Jul 03, 1964
Accession Number
AD0615065

Entities

People

  • K. Salama
  • M. Mongy
  • O. Beckman

Organizations

  • Uppsala University

Tags

Communities of Interest

  • Energy and Power Technologies

DTIC Thesaurus Topics

  • Absorption
  • Anisotropy
  • Crystals
  • Energy
  • Frequency
  • Heat Of Activation
  • Measurement
  • Polycrystals
  • Single Crystals
  • Spectra

Fields of Study

  • Materials science
  • Physics

Readers

  • Materials Science and Engineering.
  • Radar Systems Engineering.