Corrosion behavior of nickel in concentrated NaOH solutions at high temperatures in the presence of pressurized oxygen has been investigated in relation to a proposed process for waste PET to be chemically recycled. Under 5 MPa of oxygen, nickel became less corrosion-resistant as the concentration of NaOH increased at 423 K, forming Ni(OH)_2 on its surface. At 473 K, the amount of corrosion took maximum at 10 mol kg^<-1> (m) of NaOH. The corrosion product changed from Ni(OH)_2 to NiO at 30 m and the weight loss decreased. At 523, corrosion product was NiO at every concentration of NaOH but it was rather coarse below 10 m, whereas it turned dense at 30 m, decreasing the amount of corrosion. NiO layer on nickel formed in air at high temperature prior to exposure to NaOH solution also worked as a corrosion barrier. Several materials such as inconel and hasteloy were also tested and inconel was found to be most resistant against corrosion.

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Used European automobile parts, starters and alternators, were rebuilt to reuse the ones in this study. We present technologies on rebuilding, that are taking parts apart, washing, processing, painting, assembling, and inspecting. Furthermore, the rebuilding cost is calculated on the basis of the time required and the necessary expenses.

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It is necessary to remove the form error of the reference flat from the interferometer datum for improving the accuracy of the spherical profile measurement using interferometers. For this purpose, a new method called the 2 position- 4 point method was proposed. In this method, form error of the reference flat along a closed circle can be removed. Data points along the circle are necessary for the data processing of this method. However, phase-measuring devices in most interferometers are square-grid detectors, and the data need to be conversed to polar grid array. In this paper, a method is presented to improve the accuracy of the data conversion.

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The understanding of the effect of microstructures on the magnetic domain and the magnetic domain wall is most likely to lead to development of practical magnetic materials which have desired magnetic properties. In this study, magnetic domain structures in some soft magnetic materials have been observed by a Kerr microscopy and the Lorentz microscopy in order to clarify the effect of grain boundaries (GBs) on the magnetic domain structure and the magnetic domain wall motion. The GB character, the misorientation and orientation of GB plane were analyzed by an FE-SEM/EBSP/OIM system. It was found that the nucleation of reverse domains in the vicinity of the GB depended on the inclination of the GB plane. The Lorentz microscopy observation has revealed that the GB has a strong pinning effect against domain wall motion when a segment of domain wall is located on the GB plane.

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In this study, the mechanical properties of shape memory alloys, Ni_<2.1>Mn_<0.9>Ga and Ti51at%Ni were investigated. Ni_<2.1>Mn_<0.9>Ga was a ferromagnetic shape memory alloy which indicated magnetic field-induced shape memory effect, and Ti51at%Ni was known as a typical shape memory alloy. The temperature dependence of the sound velocities were measured using an ultrasonic pulse echo measurement. Experimental results show that the velocities decreased at the temperature of the transformation.

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A novel concept of using "peltier element" modules for heating and cooling the Shape Memory Alloy (SMA) is invesigated to examine the feasibility of reducing the response time for thermal cycling. Active profiles of SMA actuator are presented for each of the heating / cooling methods as well as estimate of total response time needed to complete an entire thermal cycle for artificial heart.

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This paper describes a work on the development of an artificial sphincter actuator for the treatment of the functional disorder on bowel movement. The prototype acuator is composed of two shape memory alloy (SMA) plates with all-round shape memory effect (ARSME) ; the shapes of those plates are transformed from straight to arc in the heating process and reversed in the cooling process. This actuator is expected to work as a valve of a digestive canal. Its thermo-mechanical properties including the deformation and force generated during the phase transformation of SMA have been measured. The experiments on an living body show that this actuator has good self-bowel movement function.

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