Internal friction in zirconium-hydrogen alloys at low temperatures

Abstract

Using a low-temperature torsion pendulum , internal friction measurements have been performed in polycrystalline wires of high purity zirconium charged with hydrogen up to 56 at %. The internal friction spectrum shows three peaks in the tem perature range between - 195 and 120 °C. The mechanisms proposed to explain each of the peaks differ fundamentally from those proposed by other authors, and it has been found that the heights of the peaks change with time, even though the hydrogen concentration in the samples remains constant. A metallographic study of the wires has been made in order to correlate the internal friction results with the distribution and quantity of the several phases in the sample.