THERMOELECTRIC-POWER OF MELT-QUENCHED ZR-NI AND HF-NI ALLOYS AROUND 90 AT-PERCENT NI

From an extrapolation of previously reported thermoelectric power (TEP) data of Zr-Ni glasses for Ni contents below 70 at.%, large negative TEP values were expected for alloys with about 90 at.% Ni. By contrast, in the present work, large positive values (as high as + 8 muV / K in some cases) were obtained at room temperature for melt-quenched Zr10Ni90, Zr9Ni91 and Hf11Ni89 alloy ribbons either in the amorphous or crystalline state. The TEP was found to be positive and to increase monotonously from 4.2 K to 320 K with a broad maximum around room temperature. These anomalously large positive thermopower data are suggested to be explained based on ideas developed for crystalline solid solution alloys of Ni with early transition metals.