We have studied self-diffusion in the bulk metallic glasses Zr sub 46.75Ti sub 8.25CU sub 7.5NI sub 10Be sub 27.5 and Zr sub 65CU sub 17.5Ni sub 10Al sub 7.5 by means of the radiotracer method. DIffusion of 63Ni has been investigated as a function of temperature in both alloys and also as a function of hydrostatic pressure in Zr sub 46.75Ti sub 8.25Cu sub 7.5NI sub 10Be sub 27.5. WIth the isotope 95Zr diffusion studies of the major component Zr were performed in Zr sub 46.75Ti sub 8.25CU sub 7.5NI sub 10Be sub 27.5. The diffusivity of 95Zr is much smaller than that of 63NI. The temperature dependence of 63Ni self-diffusion into Zr sub 46.75Ti sub 8.25CU sub 7.5Ni sub 10Be sub 27.5 and into Zr sub 65CU sub 17.5Ni sub 10AL sub 7.5 cannot be described by a single set of arrhenius parameters, breaks in the arrhenius curves are observed. We attribute the non-linear arrhenius behaviour to the transition form the glassy to the supercooled liquid state. For the first time activation volumes of diffusion in a supercooled melt have been determined. From the pressure dependence of 63Ni diffusion in Zr sub 46.75Ti sub 8.25Cu sub 7.5NI sub 10Be sub 27.5 we get activatio nvolumes around one mean atomic volume facouring a diffusion mechanism via vacancy-like defects.
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机译：我们通过放射性示踪法研究了大块金属玻璃中Zr sub 46.75Ti sub 8.25CU sub 7.5NI sub 10Be sub 27.5和Zr sub 65CU sub 17.5Ni sub 10Al sub 7.5的自扩散。已经研究了两种合金中63Ni的扩散与温度的关系，以及Zr低于46.75Ti低于8.25Cu低于7.5NI低于10Be低于27.5的静水压力。在Zr sub 46.75Ti sub 8.25CU sub 7.5NI sub 10Be sub 27.5中进行了主要成分Zr的同位素95Zr扩散研究。 95Zr的扩散率比63NI的扩散率小得多。 63Ni自扩散对Zr sub 46.75Ti sub 8.25CU sub 7.5Ni sub 10Be sub 27.5和Zr sub 65CU sub 17.5Ni sub 10AL sub 7.5的温度依赖性不能通过单一的阿累尼乌斯参数来描述，阿雷尼乌斯破裂观察到曲线。我们将非线性阿伦尼乌斯现象归因于从玻璃态到过冷液态的过渡。首次确定了过冷熔体中扩散的活化体积。从Zr sub 46.75Ti sub 8.25Cu sub 7.5NI sub 10Be sub 27.5中63Ni扩散的压力依赖性，我们得到了一个平均原子体积周围的活化能，这些原子通过空位缺陷构成了扩散机制。
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