The texture development was investigated on aluminum leaf which was fabricated by the traditional pack and hammering method, and in which about 1500 sheets of metal foil and paper were alternately packed and beaten by a hammer. The rolled aluminum sheets of 7.1μm thick were hammered into the leaves of 0.37μm thick. The rolling texture is almost completely replaced by (001) texture which is newly developed at the final stage of hammering. The texture seems to be of compressive type and can be attributed to the prominent activation of cross slip.

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The circular blank with a hole in the center shows similar deformation mechanisms of material for cupping, bulging, hole expanding test, burring and stretch flange forming. In this report, a hole expanding test was carried out with attention to this point and the forming limit of stretch flange forming was examined of aluminum 1100-O and H24 sheets 1mm in thickness. Urethane die was used as an elastic tool so that approximately hydrostatic pressure operated on the material over punch shoulder. The experiment has shown that the pressure of the elastic tool is convenient to compress flange and prevents the material from cracking over punch shoulder. This function of the elastic tool increases the limiting drawing ratio, and hence is convenient to deep drawing, but decreases K.W.I values a little.

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Si-precipitation in a commercial purity aluminum (JIS 1050) was investigated in order to explain the reason why the maximum elongation of finally annealed sheet was obtained by the partial annealing at 275°C. The peak of elongation was not observed in 99.99% purity aluminum. Precipitated Si particles of 0.1-0.2μm in diameter were observed in the sheet annealed at 275°C, which were arranged in the form of rings of about 1μm in diameter. The diameter of rings is nearly equal to the subgrain size in sheets annealed below 200°C. Therefore, it is considered that these rings remained within the grain as a result of grain growth with increase in the annealing temperature up to 275°C and the peak of elongation occurs because of the decrease of Si concentration on the boundary and in the matrix. Elongation was larger in the sheet produced with intermediate annealing than that without intermediate annealing. α'-AlFeSi particles of about 0.2μm in diameter have been observed after the intermediate annealing. Therefore, the larger elongation is considered to be concerned with the decrease of soluted Fe in matrix.

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Geometric uniformity in the cross section of Al-12mass% Si alloy wide foils rapidly solidified by a single roll method depends on the slit shape of nozzle. The slit shape including slit clearance, slit length, slit surface, slit outlet and slit inlet was controlled. Thickness of preferable foils depends on slit clearance. Nonuniformity of slit clearance affects the shape of wide foils in the cross section. The irregularity of slit surface has little effect on the shape of thick foils in the cross section, but has a detrimental effect on the surface appearance of thin foils. Neither slit inlet nor slit length has an influence on the foil shape. Shape factors for the slit which determine the most favorable ejection pressure of the metal for marking preferable foils include uniformity of slit clearance, sound slit-tip free from cracks and suitable slit clearance corresponding to foil thickness.

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A single roll unit for rapid solidification of wide clad aluminum foils was designed and assembled. Two nozzles were attached tandem over the roll to produce clad foils. These nozzles have positional freedoms for the roll to investigate influences of the nozzle position on the clad foil formation. High purity aluminum and Al-4mass%Si, Al-12mass%Si and Zn-22mass%Al alloys were used. A molten alloy was poured by nitrogen pressure at 0.01 to 0.3MPa onto the roll rotating at 55m/s through the first nozzle, and another alloy was poured onto the first flow through the second nozzle. Clad aluminum alloy foils are succesfully prepared. A linear and undisturbed interface lies between the base foil and the overlying foil, acros which unappreciable alloying elements diffuse. The base and overlying foils are not teared each other by repeated bending.

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Causes for scattering of the tensile strength values were investigated on specimens which were cut from various parts of aluminum castings (ADC10, 12) made by die casting machines (5-20MN). The strengths of non-defect specimens are 200-350MPa. In the case where the distance along the flow of molten metal from the gate is less than 150-200mm, the strength is almost constant. But this value varies with the kinds of castings or their thickness, corresponding to the size of dendrite arm spacing. The strengths at locations beyond the above-mentioned distance are lower, and the apparent specific gravities are also lower. The strengths of specimens containing defects are under 200MPa. These casting defects are classified into lump, thin and scatter structure defect. While the lump defect reduces both apparent specific gravity and tensile strength, the thin and scatter structure defects reduce the tensile strength but hardly affect the apparent specific gravity. The tensile strength varies almost linearly with the fraction of defect area on the fracture surface. The scatter of the strength of aluminum die castings can be reduced, when they are cast under the conditions that produce defects within a certain small quantity.

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Influence of heat treatment on organic coating adhesion and corrosion resistance of chromate phosphate conversion coatings was studied. Organic coating adhesion was evaluated on the basis of peeling strength of epoxy phenol paints at peel angle 180°. Corrosion resistance was investigated by means of salt spray test and retort test. Heat treatment at 200°C lowers adhesion property and corrosion resistance of the coatings. Studies by XPS, IR and DTA before and after heat treatment show that the main composition of the coatings is CrPO₄2-5H₂O and that bound water of CrPO₄2-5H₂O is dehydrated by heat treatment at 200°C×10min. TEM observation of the cross section of the coatings shows microcrack formation by heat treatment. Deterioration of adhesion property and corrosion resistance of the coatings by heat treatment is estimated to result from dehydration and microcrack formation of the film of conversion coating.

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