Production of high-purity hafnium and the study of some its properties

High-purity hafnium samples are prepared by crucibleless zone melting in a deep vacuum. The impurity composition and microhardness of the samples are studied over their length. The electrical conductivity and thermal conductivity of hafnium samples with various zirconium contents are determined. The temperature dependences of the ultrasound absorption coefficient in single-crystal hafnium are investigated along various directions, and the causes of absorption of ultrasonic waves with frequencies of 20, 50, and 150MHz are explained.