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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.

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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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Nanocrystalline ͑n͒ Au specimens with a density of 19.4Ϯ0.2 g/cm 3 and a mean grain size of about 20 nm were prepared below 300 K by the gas deposition method, where two types of n-Au specimens were obtained as a function of a deposition rate, the type-H specimens above 800 nm/s and the type-L specimens below 800 nm/s. The anelastic and the plastic creep responses are similar qualitatively but different quantitatively between the type-H and type-L specimens. The anelastic strain an,GB , associated with the grain boundary ͑GB͒ regions, increases linearly with (TϪT an1)(ap Ϫ an1), when the temperature T is higher than a threshold temperature T an1 of 200 K and the applied stress ap is higher than a threshold stress, an1 , of a few MPa. The ratio of an,GB to the elastic strain is as large as 1.1 for the type-H specimens and 0.2 for the type-L specimens at 320 K for ap ӷ an1. The activation energy for the GB anelastic process is 0.2 eV. We surmise that cooperative motions of many atoms in the GB regions are responsible for an,GB , and both T an1 and an1 show a distribution depending on the number of atoms associated. The plastic creep rate Ј vs ap data show a letter S-like curve. We classified the creep response into three categories, region I for the linear creep rate region for ap between pc 1 and pc2 , region II for the transient creep rate region for ap between pc2 and pc3 , and region III for the saturation creep rate region for ap between pc3 and y. The threshold stresses pc1 and pc2 and the yield stress y are about 30, 150, and 360 MPa for the type-H specimens, and about 60, 300, and 500 MPa for the type-L specimens, respectively. pc3 is slightly lower than y. From scanning tunneling microscopy images, we surmise that the localized GB slip takes place in region I, and the mean separation between the localized GB slips decreases with increasing ap in region II and becomes comparable with the mean grain size in region III. The plastic creep in region III may be explained by the Ashby creep. The present view for the creep behavior explains the low-temperature creep behavior of fcc n metals.