Small atom diffusion and breakdown of the Stokes–Einstein relation in the supercooled liquid state of the Zr46.7Ti8.3Cu7.5Ni10Be27.5 alloy
نویسندگان
چکیده
Be diffusivity data in the bulk metallic glass forming alloy Zr46.7Ti8.3Cu7.5Ni10Be27.5 are reported for temperatures between 530 and 710 K, extending 85 K into the supercooled liquid state of the alloy. At the glass transition temperature Tg, a change in temperature dependence of the data is observed, and above Tg the diffusivity increases more quickly with temperature than below. The data in the supercooled liquid can be described by a modified Arrhenius expression based on a diffusion mechanism suggested earlier. The comparison with viscosity data in the supercooled liquid state of Zr46.7Ti8.3Cu7.5Ni10Be27.5 reveals a breakdown of the Stokes–Einstein relation, indicating a cooperative diffusion mechanism in the supercooled liquid state of Zr46.7Ti8.3Cu7.5Ni10Be27.5 . © 1996 American Institute of Physics. @S0003-6951~96!04643-8#
منابع مشابه
SMALL ATOM DIFFUSION AND BREAKDOWN ON STOKES-EINSTEIN RELATION IN THE SUPERCOOLED LIQUID STATE OF Zr-Ti-Cu-Ni-Be ALLOYS
Be diffusivity data in the bulk metallic glass forming alloys Zr4i.2Ti13.sCu125Ni10Be22.s and Zr46.7Tis.3Cu75Ni10Bez7.s are reported for temperatures between 530K and 710K, extending up to SOK into the supercooled liquid states of the alloys. At the glass transition temperature, T g' a change in temperature dependence of the data is observed in both alloys, and above T g the diffusivity increas...
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