For melt-spun amorphous (a-)Cu 50 Ti 50 and a-Pd 80 Si 20 , crystallization under electropulsing was studied by means of the discharge of a condenser with initial current density i d0 of the order of 10 9 A/m 2 and decay time in between 2 and 0.1 ms, where a specimen was sandwiched by AlN/BN substrates to minimize an effect of joule heating. The crystallization proceeds during electropulsing when i d0 is higher than the threshold i d0,c. Here i d0,c is a function of and shows a minimum value of 1.4ϫ10 9 A/m 2 at ϳ2 ms for a-Cu 50 Ti 50 and 2.6ϫ10 9 A/m 2 at ϳ0.9 ms for a-Pd 80 Si 20 , where the maximum increase in temperature during electropulsing is about 120 K for a-Cu 50 Ti 50 and 50 K for a-Pd 80 Si 20 , respectively. One-half of the specimen volume crystallizes after a few repetitions of electropulsing with i d0 beyond i d0,c for a-Cu 50 Ti 50 and after several repetitions for a-Pd 80 Si 20. We surmise that for the density fluctuations existing in amorphous alloys, under electropulsing a high-density region undergoes a resonant collective motion as a whole, which induces migrational motions of atoms in the low-density matrix around it. For a-Pd 80 Si 20 , it is observed that an unknown phase was formed in the early stage of the crystallization under electropulsing and disappeared after further electropulsing. It is also found for a-Cu 50 Ti 50 and a-Pd 80 Si 20 that for electropulsing with high i d0 , the electrical resistivity of a specimen decreased at the early stage of the crystallization and then turned to increase for further electropulsing. These phenomena may be associated with changes in the thermodynamic free energy of phases under an electric current predicted by the theoretical works. We surmise that present electropulsing excites a resonant collective motion of many atoms and modifies the thermodynamic free energy of phases too.
The vibrating reed technique applicable to the elasticity measurements for the metallic films of nm thickness deposited onto reed substrates and its application to vacuum‐deposited aluminium films are reported: Young's modulus of the aluminium films EA1,f shows a good agreement with that of bulk aluminium EA1,b for films of thickness d > 100 nm. For smaller d, FA1,f decreases from EA1,b with decreasing d, especially for d < 10 nm. The decrease in EA1,f is tentatively attributed to the increasing, effects of interfaces between crystallites in the films. The results of internal fricition observed for films of about 50 nm thickness are very similar to those for the films of 100 nm reported by Berry, i.e. the strong decrease in the peak temperatures of the so‐called grain‐boundary relaxations is observed.
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