Numerical simulations and experimental studies are carried out to understand the deformation process of thin polymer film in nanoimprint lithography. Deformation of a thin polymer above its glass transition temperature is studied for various imprinting conditions such as the aspect ratios of a mold pattern, initial thickness of the polymer, and imprinting pressure. Cross-sectional profiles of the deformed polymers are simulated by the finite element method based on a rubber elastic model. The results are compared with experimental data. The areal penetration ratio of the polymer into the recessed groove of the mold and residual thickness underneath the mold are quantitatively evaluated. The simulations and the experimental results agree well with each other.

Compressive tests were made for the as-cast Cu 45 Zr 45 Al 5 Ag 5 bulk glassy alloy rods with a diameter of 3 mm at 298 and 77 K, at an initial strain rate of 5 Â 10 À4 s À1 . It was found that at 77 K, the compressive yield strength, maximum strength and plastic strain to fracture of the glassy alloy rod are higher than those at 298 K. The maximum strength measured at 77 K is about 13% larger than that measured at 298 K. In particular, its plasticity at 77 K is significantly enhanced. SEM observations reveal that more shear bands appear near the fracture plane at 77 K. The higher strength and ductility at a cryogenic temperature (77 K) are probably due to the lower mobility of the squeezed free volume.

Since the invention of bulk glassy alloys, a number of studies have been performed at ambient temperatures or above. However, little is known about mechanical properties of bulk glassy alloys at cryogenic temperatures. In this study, we investigated the effects of temperature and strain rate on the mechanical properties of a Cu 45 Zr 45 Al 5 Ag 5 bulk glassy alloy fabricated by high pressure die casting methods. Compression tests were performed for the Cu 45 Zr 45 Al 5 Ag 5 bulk glassy alloy rods with a diameter of 3 mm at temperatures of 298, 223, 173 and 77 K and at strain rates from 5 Â 10 À5 to 5 Â 10 À3 s À1 . It is found that the maximum compressive stress and plastic strain to failure increase monotonically with decreasing testing temperature. Multiple shear bands are observed on the side surface of the specimen deformed plastically at cryogenic temperatures. The maximum compressive stress and plastic strain are almost independent of strain rate. The reason for the changes in the maximum compressive stress and plastic strain with temperature and strain rate is discussed.

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Steelmaking slag has been used in the coastal area for the purpose of the environmental improvement. Short-term alkali elution behavior induced by free CaO in the steelmaking slag was investigated by a batch and continuous vessel. In this study, long-term alkali elution experiments were done in an open channel vessel with a slag box to make clear the decreasing mechanism of the alkali elution from steelmaking slag into seawater. The experimental period was 44 d (1056 h). The pH values increased just in the beginning of the experiment, and then gradually decreased in about 100 min. They showed almost the same value as that of seawater in 1200 min. As the experimental time passed, the white deposits on the steelmaking slag layer, which were composed of Mg[OH] 2 and CaCO 3 , spread to the lower slag zone in the slag box. The white deposit zone of larger slag size was more rapidly diffused downward than that of smaller one due to larger voidage in the slag layer. While carrying out the batch test with the used slag by the long-term experiment, the alkali elution rate of slag layer on the open channel flow was 0.03-0.11 times decreased compared with the unused slag, whereas that of the lower positioned slag layer was 0.10-0.38 times decreased. From these results, it was found that the alkali elution rate was reduced by the white deposit on the steelmaking slag.