Dislocation Relaxations in Metals and Single Crystal Quartz

Abstract

During the last several years, a number of ultrasonic attenuation measurements have been made in face centered metals which show attenuation maxima at temperatures related to the metal and the measuring frequencies. The first of these measurements were made by Bordoni [1], and other measurements were made by Bömmel [2] and Welber [2]. For lead at a frequency of 10.1 Kc, Bordoni’s measurements are shown by fig. 1. All measurements reported are for strains of 10⁻⁸ or less. The data of fig. 1, which is typical of other metals, show an attenuation peak followed by an attenuation which increases exponentially with the temperature. The activation energy for lead is 4350 calories/mole. Fig.2 shows the details of the low temperature peaks found by Bordoni for four face centered metals. Mild cold work increases the height of the peaks.