Using an isothermal rolling machine with a twin roll caster, sheet materials were fabricated with a thickness of t=0.5 mm from three types of magnesium alloy sheets(namely, AZ61, AZ91 and AM60). The result indicates that sheet materials with a limited number of edge cracks can be fabricated from any of these magnesium alloys by rolling at Tr=300°C or higher. Next, the deep drawability of the thus-obtained rolled thin sheets were examined. Regardless of the type of magnesium alloy, the limiting drawing ratios(LDRs)improved the most for the magnesium alloy sheets rolled at Tr=300°C, at which a uniform and very small grain diameter was obtained. Moreover, the LDRs of AZ61, AZ91 and AM60 sheets rolled at Tr=300°C were 2.7, 2.4 and 2.6, respectively. It became apparant that these magnesium alloy sheets have characteristics sufficient for practical use in deep drawing when rolled under appropriate conditions.

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Aluminum anodic oxide film with a two-layer structure was successfully prepared by a two-step anodic oxidation process in two solutions of phosphoric acid (H₃PO₄) and sulfuric acid (H₂SO₄). The two-layer structure consists of the upper layer with wide pores and the lower layer with narrow pores. Subsequently, titanium dioxide (TiO₂) was electrodeposited into wide pores in upper layer. The TiO₂ content in the obtained sample depended on the concentration of TiO₂ sol, pH and the migration voltage during electrodeposition. The hardness, corrosion resistance and sealing degree of the sample with TiO₂ were almost the same as that of the sealed sample without TiO₂. On the other hand, the electron spin resonance (ESR) measurement indicated that hydroxyl radicals (·OH) were generated from the prepared sample by the irradiation of ultraviolet light. Furthermore, antimicrobial activity to Escherichia coli of the anodic oxide film of aluminum electrodeposited TiO₂ was higher than that without TiO₂. These results suggested that the two-layered anodic oxide film of aluminum electrodeposited with TiO₂ would be a novel photocatalytic antimicrobial material.

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The ultrasonic vibration cutting is a processing method by small serration collision of tool and work piece. 50 years passed, after this working method was advocated. Recently, this working method is not always clear on hoop again notice begin to and the cutting mechanism. This study described ultrasonic vibration cutting of titanium base alloy (TAB6400). The turning by vibration cutting and conventional cutting was carried out in order to clarify the cutting mechanism of the ultrasonic vibration cutting. The following were observed: cutting force, tool wear, surface roughness, tools edge temperature and chip shapes. As a result, the vibration cutting was found to lower cutting force, and the tool wear was proved to be suppressed. However, the remarkable effect on the surface roughness could not be observed. They were also flowing and good cutting on the chip form. Ruggedness was observed in edge side of which the chip shape seemed to be features of the vibration cutting. From above ultrasonic vibration cutting of the titanium base alloy under limited condition, clarified the effectiveness though.

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Trace nickel addition improved a property of aluminum bonding wire. Recently some investigators reported equilibrium solid solubility of Ni to Al smaller than previous values. Therefore, its re-investigation is necessary. Wire and sheet of Al–Ni dilute alloys were prepared with total impurity contents less than 15 ppm. After heat treatments at temperatures above 523 K, electrical resistivity was measured at 77 K and 300 K by four contacts DC potentiometry and density-mass method size factor. Resistivity at 77 K, ρ_D77, after solution treatments showed a good linear relation to Ni contents up to 310 ppm. The 438 ppmNi specimen of the highest content showed a smaller ρ_D77 than the straight line, suggesting incomplete dissolution of Ni. Contribution per unit concentration of Ni to the ρ_D77, Δρ₇₇^Ni, was 10.4±0.2 nΩm/mass%. Resistivity values at 300 K, ρ_D300, were at maximum only 1.7% higher than that of ideally pure aluminum. Though linearity of the line was poor, Δρ₃₀₀^Ni was 8.86±1.09 nΩm/mass% and still higher than the Fink et al.'s value. The equilibrium solubility of Ni determined at temperatures ranging 723 K to 913 K is expressed as C_eq^Ni/mass% = 1.36×10⁴ exp(−1.16×104/T), giving maximum solubility about 20% lower than Fink et al.'s.

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