Plastic deformation, vacancy diffusion, and vacancy delocalization in bcc 3He.
نویسندگان
چکیده
The plastic deformation of bee 3He crystals has been studied near the melting curve, in the temperature range 0.65 K :::; T:::; 1.17 K, and for strain rates, E, from 2X 10to 2X 10sec-I. The resulting relations between strain rate and stress, at a given temperature, are accounted for in terms of dislocation climb and vacancy diffusion in the solid He. The temperature dependence of the strain rate at a given stress indicates that a nonclassical mechanism underlies the deformation process. The vacancy diffusion coefficient in bee 3He, as a function of temperature, is deduced from these results, and an energy bandwidth for delocalized vacancies of 0.24±0.05 K is obtained through a fit to theoretical predictions.
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ورودعنوان ژورنال:
- Physical review. B, Condensed matter
دوره 33 3 شماره
صفحات -
تاریخ انتشار 1986