Internal Friction in Hydrogen Charged Aluminum Alloys

Abstract

<p>Measurements of the internal, friction of several aluminum alloys were made over the temperature range from 80 to 300 K using the two component resonator technique. The technique was improved, by using a metallic bond between the two components, so that measurements in the Qˉ¹ ≃ 10ˉ⁶ range could be made at three frequencies. Preliminary experiments using quartz crystals as specimens were performed in order to check the properties of the metallic joint. A method of checking the bond, by measuring the resonator properties at about half the fundamental frequency of the quartz transducer alone, was developed.</p> <p>Comparisons of the internal friction spectra of hydrogen charged samples with spectra of vacuum annealed samples were used, in conjunction with a simple model of the distribution of hydrogen, to determine upper limits on the binding energy between hydrogen and substitutional solutes in the aluminum matrix.</p>