Heat treatment effecta in amorphous metals Zr70 Cu30 AND La70 Cu30

Abstract

We measured the electrical resistivity (4—300 K), superconducting critical temperature and thermal conductivity (0.5—7 K) of the amorphous metals Zr7o Cu3o and La70 Cu30 - Heat treatments below crystallization temperature induced changes in these properties. In particular, in the first stage o f the annealing of Zr70 Cu3o there are systematic changes in the thermal conductivity and the critical temperature, while the electrical resistivity remains constant. We show that there is no simple correlation between the thermal conductivity processes in the low temperature and plateau regions. We also show that the thermal conductivity of as quenched La70 Cu3o is typical of amorphous metals, contrary to information previously reported.