Flow of water from a pouring equipment with a quick tilt-center up-down mechanism by the two stage air cylinder were studied experimentally. When the down stroke of the tilt-center was increased by the two stage motion of the air cylinder and returned to the stroke of the single motion, the flow rate at the start of pouring increased further than single motion with no change of the total pouring volume. Experiments on the flow of water in the gating system from the pouring equipment with the above mechanism were carried out. The experimental data showed that the liquid level in the pouring basin rose up more rapidly than the case of the single cylinder motion.

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  The initial solidified phase, such as coarse α phase and scattered chill structure, affects the flow length of the aluminum die casting alloy. The effects of initial solidified phase on the flow length of ADC12, ADC10 and AC2A were investigated using a cold chamber type die casting machine. The flow length decreased with the area ratio of the initial solidified phase. The structure of the initial solidified phase also affects on the flow length. The deviation of flow length increased with the content of Si. The critical solid fraction of fluid flow was also estimated using the relationship between the initial solidified phase and flow length. The critical solid fraction of fluid flow was about 0.6.

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  The contact of SiC particles with molten Al-Si-Cu alloy may result in Al₄C₃ formation in the electron beam remelting of aluminum alloy matrix composites, depending upon the matrix composition. It is known that the formation of Al₄C₃ is affected by melt temperature, holding time and silicon content in the matrices, and also high silicon levels are required to prevent the Al₄C₃ formation. However, the influence of copper content on the Al₄C₃ formation has not been clear. Therefore, the influence of silicon and copper content on the Al₄C₃ formation was studied, and the following results were obtained: high copper and low silicon content promote the Al₄C₃ formation in electron beam remelting. The formed plate-like Al₄C₃ prevents the bead surface from smoothing.

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  The age-hardening process of Al₂O₃ continuous fiber reinforced Al-Si-Cu and Al-Si-Cu-Mg alloys was investigated by using a TEM, DSC, Vickers macro hardness tester and EPMA. A series of composite specimens were solution treated at 773 K for 10h, and subsequently aged at 433 K and 473 K for 10 min to 10⁴ min. The aging characteristics of the composites were compared with those of the unreinforced alloys which were cast and heat treated under identical conditions as the composites. Although the precipitation of composites is accelerated, the over-all age-hardening sequence is similar to that of unreinforced alloys. In the case of Al₂O₃ / Al-Si-Cu alloy composite, the degree of age-hardening (ΔHV = HV. max-HV. s) is higher than that of unreinforced alloy, because the θ’ phase precipitated preferentially on the dislocations is more uniformly dispersed in the composite with higher density of dislocations. On the contrary, in the Al₂O₃ / Al-Si-Cu-Mg alloy composite, the λ’ phase homogeneously precipitates in the α matrix independent of dislocations. However, the precipitation amount of λ’ phase is decreased due to the prior formation of MgAl₂O₄ (spinel) at the interface between the Al₂O₃ fiber and matrix alloy. Therefore, the precipitation rate is almost unchanged and the degree of agehardening is slightly decreased by the presence of Al₂O₃ fiber.

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  When oolitics adhere to green sand, it becomes waste green sand. Green sand is reclaimed for the purpose of mainly peeling off the oolitics. In this study, we reclaimed oolitics sand by 3 representative processes, calcining + friction reclamation, friction reclamation, and grindstone reclamation. Calcining + friction reclamation is more suitable for the shell mold process, and friction reclamation for the cold box process. The change of waste green sand in calcining + friction reclamation was as follows : the total clay changed to oolitics after calcining. This oolitics and that adhered to the waste green sand from the beginning were removed by friction reclamation. When the respective oolitics were removed, the reclamation sand showed the same strength as the new sand, indicating the end of reclamation can be determined from the oolitics quantity. Also, when the sand is reclaimed by friction reclamation, the strength is higher than the new sand because the sand shape is improved.

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  When cutting conditions, such as cutting speed, the feed and depth of cut in machining are increased, the cutting efficiency greatly improves. An increase in cutting conditions, however, does not necessarily decrease cutting costs as an increase in cutting conditions results in shorter tool-life. This study examined the relationship between the turning of gray cast iron in cutting conditions such as cutting speed, feed and depth of cut, and reduction of cutting costs. Cutting conditions such as feed and depth of cut are incorporated into “Taylor's tool-life equation” to obtain (VF^l D^m Tⁿ ＝ C). This equation was used to determine and examine an economic cutting speed which minimizes cutting costs and the minimum cutting cost.

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