Comment on “Oxidation of Hafnium and Diffusion of Hafnium Atoms
نویسندگان
چکیده
In his paper, Chandi C. Dey reports on the measurement of the nuclear quadrupole interaction of 181Hf(β−)181Ta in α-Hf metal with a few percent zirconium heated in air by perturbed angular correlation (PAC) of γ-rays. Since he did not observe the formation of HfO2 up to 773 K and during initial heating at 873 K for one day, he concluded that no oxygen is absorbed. The time dependent hyperfine interaction was therefore attributed to the diffusion of hafnium atoms. The transformation from α-Hf to HfO2 did not follow an Arrhenius-law, contrary to his expectations. Furthermore, he attributed the time dependent hyperfine interaction in HfO2 to the diffusion of hafnium atoms. This interpretation is in sharp conflict with existing data as will be discussed below.
منابع مشابه
Reply to Comment of Professor T. Butz on ``Oxidation of Hafnium and Diffusion of Hafnium Atoms in Hexagonal Close-Packed Hf; Microscopic Investigations by Perturbed Angular Correlations'' by Chandi C. Dey, Z. Naturforsch. 67a, 633 (2012)
Prof. Butz in his comment basically argued that the fluctuation observed in hafnium metal after heating at 873 K for two days in air is due to oxygen atoms and not due to hafnium atoms as wrote in the paper. But I don’t agree with his views on this point because of the two following arguments: i) In fact, the relaxation effect arises due to fluctuation of atoms, ions or molecules near to the pr...
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