Lubricant oil is always used to improve or enhance the deep drawing limit and prevent the damage on the surface of cylindrical parts. Therefore, the oil on cylindrical parts must be cleaned by cleaning agent after deep drawing. Not only the cost of lubricant oil and the cleaning is needed, but also the lubricant oil and cleaner affect the environment of the earth. The authors have created the new deep drawing method to prevent the global environment. High pressure jet water is adopted on the new deep drawing instead of the lubricant oil. The water viscosity is low and the water itself is not suitable for lubricant. But the high pressure water jet is compulsorily supplied to the gap between the die and sheet metal, and strong lubricant membrane is produced in the gap. The effects of the deep drawing conditions are experimentally examined on the new deep drawing using high pressure jet water. Therefore the capability and character of the drawing are made clear in this study.

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The hydroxyl radical generated from aluminum anodic oxide film by UV irradiation was evaluated using ESR measurement and its antimicrobial characteristic was also investigated using a photoirradiation film contact method. DMPO-OH adduct was detected by ESR measurement with DMPO (5,5-Dimethyl-Pyrroline-N-Oxide) as a spin trap reagent when aluminum anodic oxide film was irradiated by UV. In regard to bactericidal activity to E. coli using photoirradiation film contact method, it decreased the number of the survived E. coli by photoirradiation. From these results, it found that hydroxyl radical generated from aluminum anodic oxide film and that the aluminum anodic oxide film had antimicrobial action by photoirradiation.

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High-magnesium Al–Mg alloys are known to be sensitive to the stress corrosion cracking (SCC) involving environmental hydrogen, invading from the corrosive environment. In this study, the behavior of the environmental hydrogen in solution-treated Al–6 mass% and 8 mass%Mg binary alloy sheets stretched by 10% during exposure to 3.5%NaCl aqua solution has been investigated by means of hydrogen microprint technique (HMPT). Microprint image is observed on one surface while the other exposed to the corrosive solution. In both the alloys, the silver particles corresponding to the sites where hydrogen atoms are emitted from the inside of the alloys are observed on many slip lines and some grain boundaries. It is shown that the hydrogen atoms are transported with moving dislocations in the alloys. The environmental hydrogen can be generated because of chemical reaction of water in the solution with the bare aluminum introduced by the plastic deformation, and then included in the alloys.

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In the bulging, the material existing at the flange portion is not drawn into the die opening, and so the contour of a metal sheet does not change. This feature of the bulging is advantageous to producing cups with wide flange. On the other hand, there is a weak point that it is difficult to make cups with large height by the bulging. In this study, in order to improve the bulge height, the method for flowing the material of the flange region to the die hole was examined. A new processing combined bulging, reverse re-bulging and ironing was tried. Variations of thickness strain distribution by each process were measured and the effectiveness of the process was clarified. Finally, it was possible to make a bulged cup about 3.1 times as high as that made by conventional stretching.

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