A1100P-0 and -H24 sheets 2.0, 2.5 and 3.0mm in thickness were punched with urethane elastomer pads and an opposed punch 30mm in diameter under high static pressure. The urethane elastomer spring's force acted on the opposed punch as a reaction of elastomer pads' pressure. The ratios t_r (=t'/txx100) of fracture surface t' to sheet thickness on the 0- and H24-sheets under the maximum opposed punch force are 3.5 to 4 times end 1.5 to 2 times as large as those where no opposed punch is used. The ratio t_r on the H24-sheet 3.0mm in sheet thickness is 72%. The difference Δd (=d'-d) (mm) between die hole diameter d and punched hole diameter d' in the sheet 3.0mm in thickness under the maximum opposed punch force are -0.23 on the 0-sheet and -0.10mm on the H24-sheet. The edges of punched sheets and the tolerance of punched holes can be improved by the use of urethane elastomer pads and an opposed punch under high static pressure.

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Al-4%Cu and Al-2 and 5%Si alloys were solidified under high pressures up to 2000kgf/cm². The eutectic liquid having low freezing point is condensed in the terminal freezing region and causes anomalously devedoped segregation in the shape of a withered bush. Segregation occurs noticeably when the compressing direction is perpendicular to the preferential growth direction of columnar crystals. Segregation hardly occurs when compression and prefered growth are in the same direction. Gravity castings solidified under normal pressure have more of eutectic phase near the side surface in the form of inverse segregation. The residual liquid eutectic in the solidifying castings under high pressure is, on the other hand, squeezed into the central and upper region of the castings where the liquid with large solidification contraction remains resulting in normal segregation extremely accelerated.

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This dry wear test intended to examine influences of a sampling direction to the wear characteristics and the wear mechanism. Both the wear characteristics and the wear mechanism of 5083 alloy are independent of the sampling direction. Severe sticking of Fe occurs on the sliding surface in the low velocity range. Fe is activated in the range and is easily oxidized by air to form ferrous oxides. As the sliding velocity is accelerated, a part of the alloy is heated up to a molten condition by the frictional heat. If slight metal transfer to the rotor occurs in the initial stage of higher velocity range, fused 5083 alloy acts as a lubricant and decreases wear loss. Considerable metal transfer to the rotor occurs in the higher velocity range resulting in mutual friction of 5083 to 5083 alloy. Heavy adhesion and fusion increase the wear loss.

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The solidfied structure and phase decomposition during tempering of splat quenched Al-Hf alloys were electron microscopically examined. The solid solubility of Hf in the splat quenched Al-Hf alloy extends up to 10%. The grain boundary mobility of the splat quenched Al-Hf alloy is so high that discontinuous precipitation caused by a grain boundary reaction preceds continuous precipitation within grain. Precipitates formed by the grain boundary reaction are fine needle-shaped and have a metastable crystal structure. When the alloy solidifies at a slow rate, an angular precipitate forms within a grain. The microstructure of the angular precipitate and the interaction between moving grain boundary and the precipitate are discussed.

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Soft aluminum sheets were deep drawn using a paraffinic mineral oil containing oiliness agents. The limited drawing ratio, the amount of metal transfer adhered to the die surface and the surface condition of drawn cups were measured. The limited drawing ratio at low drawing speed increases by the use of oiliness agents in the lubricating oil. Both the base oil and the lubricating oil containing additives have nearly the same effect on the limited drawing ratio at high drawing speed. The surface damage of drawn cups and the amount of metal transfer of worked materials adhered to the drawing die markedly decrease with increasing thethe us drawing speed and by e of oiliness agents. Oleic acid and stearic acid are effective to a greater degree. Ester having longer carbon chain on the higher fatty acid sides is more effective than that on the higher alcohol sides.

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