Results of FFT analysis of the noise generated during the shake-out of iron castings showed that the power spectrum prior to actual shake-out starting is close to that of the consolidated vibration of the shake-out machine and molding flask. On the other hand, after shake-out completes, the power spectrum closely resembles to the characteristic frequency of the molding flask. Based upon the above results, a formula to allow the relationship between the time and the power spectrum was obtained by approximation. Using the formula obtained, the time when the shake-out starts and the time it ends are calculated, and the actual shake-out time can be estimated.

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  This study discusses the effects of the graphite shape and the temperature change on the tensile properties through static tensile tests conducted on three kinds of ferrite base cast iron in which the graphite shape is flake, vermicular and spheroidal (hereafter referred to as FC, CV and FCD, respectively). By reason that FCD was the most susceptible to the effects of temperature rise on the tensile strength, a steep lowering in the strength was observed in FCD after the temperature exceeded 723K. On the contrary, FC was the least influenced by those effects. The effects of temperature rise on elongation was found to be low in FC and CV, while FCD was extremely affected due to blue brittleness at around 673K. It was revealed that cast iron, unlike general steel materials, essentially presented a higher value in the elongation than the reduction of area. In the case of cast iron, it is therefore reasonable to use its elongation than the reduction of area as the index for representing the degree of ductility of the material.

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  The possibility of applying the Ohno continuous casting (OCC) process for fabricating Cu-based shape memory alloy wires was examined using Cu-14.1 mass % Al-4.2 mass % Ni alloy. Most of the cast wires, 2mm in diameter, were found to have unidirectional structures with a matrix phase of β₁ in which fine γ₂ particles were dispersed. It was found that at a lower casting speed range (0.8∼1.5 mm/ s), the cast wires showed shape memory effects arising from stress-induced martensitic transformations. At higher casting speeds (1.8∼2.5 mm/s), the cast wires produced exhibited super elasticity at room temperature. In addition, the fatigue failure of the cast wires (casting speed : 2.5 mm/s) occurred after 6500 of cycles of bending.

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  Two kinds of rheocast 7075 aluminum alloy small billets with a fine globular structure or a fine dendrite-dispersed one could be obtained by mechanical stirring at the position extremely near or slightly remote from the solid-liquid interface during solidification, respectively. At ram speed of 1 mm/s, both kinds of the rheocast billets could be extruded in semi-solid states to the round bars with smooth surfaces, while numerous surface cracks reaching inside generated at the case of the billets cast into metal mold. In all billets, extrusions were proceeded by some leaks of liquid phase, which resulted in the lowering of strength for the round bars by the significant loss of solute concentrations as zinc and copper in them. Such liquid leak was suppressed by increasing ram speed to 5 mm/s in the rheocast billet and the hardness of the bars after T6 treatment compared with the one for hot extrusion product.

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  The releasing force of ADC10 die castings was measured using ejector pin type pressure sensor and the microstructure was observed in order to investigate the effect of Fe and Mn on the releasing ability. Inverse segregation with concentration of Fe, Mn and Si a two or three time higher than the average composition of Fe, Mn and Si was observed. Intermetallic compounds of Al₅FeSi were observed at the surface of die casting added with 0.8 mass % Fe. Granular intermetallic compounds of Al₁₅ (Fe, Mn)₃ Si were observed at the die castings surface added with 0.8 mass % Fe and 0.4 mass % Mn. The hardness of the casting surface layer was increased by the inverse segregation of the intermetallic compounds. The releasing force of die castings without Fe and Mn increased with increasing of casting amount increased. The releasing force of the die castings which contain 0.8 mass % Fe and / or 0.4 mass % Mn did not increase.

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