Abstract: The torsional deformation properties of a TiNi shape-memory alloy thin strip were investigated. The results are summarized as follows. (1) The martensitic transformation starts at the edge of the thin strip. (2) The fatigue life in pulsating torsion is longer than that in alternating torsion. (3) A simple rotary driving element can be developed by using SMA-thin strip torsion.
Abstract: The SMC belt composed of two kinds of SMAs and SMP was fabricated and the three-way movement and recovery force in bending were investigated. The results obtained can be summarized as follows. (1) The three-way bending movement was achived during heating and cooling based on the characteristics of the SMA tapes and the SMP sheet. (2) The recovery force increased during heating and decreased during cooling. The recovery force was evaluated by the proposed simple model.
Abstract: In this work magnetic nanorods have been synthesized by electrodeposition inside the nanotubes fixed to anodic alumina oxide (AAO). The used templates have the pore diameter of 120 nm. In the first step different combinations of 3d elements oxide nanotubes such as: CoO, NiO, NiFe2O4, CoFe2O4 and Fe3O4, have been successfully fabricated inside the nanopores by wetting chemical deposition followed by thermal decomposition. Oxide/Fe, wires were obtained in the next step by electrodeposition The morphology of obtained structures were studied by atomic force microscopy (AFM) and scanning electron microscopy (SEM). The magnetic properties of the nanostructures were determined on the base of behavior of the structures in external magnetic field. Local magnetic moment orientation is not strictly determined up to now. The potential biological application as an enzyme carrier was tested.
Abstract: Young's modulus of coat films has been estimated by using the double-beam vibration-reed method. The 18-8 stainless steel (SUS304; JIS) sheets coated by some inorganic films were prepared by using the sputtering and CVD. The method are applied to estimate the modulus by using the fundamental mode resonant frequencies of coated substrate before and after deposition of the films. The resonant frequency of each sample was measured by shaking the sample, and the displacement response detected by the eddy current displacement sensor. The specimens include non-coated stainless, TiO2, CrN, TiN, and diamond-like carbon(DLC) coated sheets. The thickness of the coat films range from 0.4 to 3.5. The non-coated substrate specimen requires an adequate annealing corresponding to the thermal history of the film deposition. The measured resonant frequencies have some amplitude dependencies, therefore the frequencies were extrapolated to zero amplitude. The extrapolated frequencies, the modulus of the annealed substrate, density and the geometrical parameters were assigned to the formula of the resonant frequency for the double-beam. The measured modulus of SUS304 substrate, TiO2 and TiN films are smaller than bulk form. The measured modulus for the CrN film is larger than the one form the literature data. The modulus of DLC film falls onto the range of literatures.
Abstract: The single crystals were produced from industry zinc alloy containing 0.075wt.% of titanium and 0.15wt.% of copper. The Bridgman method was applied to obtain the single crystal. Three growth rates were used: 6mm/h, 10mm/h and 16mm/h. The common feature of all of the produced single crystals was homogeneous distribution of the second phase on a sections normal to the growth direction. The investigated single crystals were deformed in compression test with jump changes of the strain rate (from 10-4s-1 on 10-3s-1). From the obtained stress-strain curves the Critical Resolved Shear Stress (CRSS), hardening coefficient in the easy slip range (QA) and thermodynamical – activation volume (V*) and activation enthalpy (DH) were determined. The tests were done at the temperature range from 77K to 400K. Results showed anomaly on the CRSS=f(T) curve. The temperature of an extreme was 240K. The same effect was observed on V*=f(T) and DH=f(T) curves. The presented results reveal good correlation with crack phenomena that was observed during a bent of the zinc alloy sheets at the temperatures below 300K.