Rapidly solidified Mg-Al-Zn alloys were prepared by the single role melt-spinning method. It is well known that Mg-Al-Zn alloys consist of quasi crystals. The rapidly solidified ribbon had a width of 700 μm and a thickness of 20 μm. The structure of the ribbons was investigated by XRD and TEM, and their thermal stability was analyzed using DSC. The mechanical properties of the ribbons were measured. Some ribbons were mechanically ground. The results of the DSC analysis indicate that Mg₃₂Al₁₃Zn₃₆ alloy ribbons consist of thermally stable quasicrystals. The strength of the Mg₃₂Al₁₆Zn₃₃ alloy ribbons consisting of both the metastable quasicrystals and approximants was found to be the highest. After milling, the Mg₃₂Al₁₃Zn₃₆ alloy ribbons remained in the quasicrystal state but the other ribbons were found to change into intermetallic compounds. The Mg₃₂Al₁₃Zn₃₆ alloy ribbons were consolidated at the condition of 573 K and 250 MPa by PCS. After sintering, the quasicrystal phase transformed into approximants.

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  Effects of microstructural feature, secondary dendrite arm spacing (DAS II) and defects (mainly porosity) in aluminum alloy die castings ADC10 on tensile properties were investigated. Die castings were made using a 882kN cold-chamber die cast machine. The test pieces differed in DAS II and quantity of porosity. The tensile strength and elongation were especially found to increase with the decrease in DAS II and quantity of porosity. Fractures include ductile fracture and brittle fracture. The brittle fracture occurred more easily with higher porosity or DAS II, and the ductile fracture with smaller porosity or DAS II. The greater the specific gravity was above 2.70, the more excellent the tensile strength and quality were found to be.

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  This paper presents a method to design the optimum shape of a container and the appropriate velocity pattern considering the damping of sloshing for liquid container transfer. The sloshing phenomenon is numerically analyzed by a boundary element method (BEM). For transfers using conventional trapezoidal velocity patterns, the optimum container shape is designed through BEM simulation for various slope angles of the side or bottom wall of the container. In terms of genetic algorithm which is a well-known approach for global optimization, the optimum shape of the container was obtained by maximizing the performance index considering the resonant frequency of first-mode sloshing, the volume of liquid and the slope angle of the side wall. In addition, it was shown that residual sloshing was effectively suppressed by adjusting the acceleration (deceleration) time of container transfer to the period of first-mode sloshing.

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  The carbon equivalent of high strength cast iron melt with rare earth elements and manganese was changed variously and the mechanical properties of these specimen were examined. In addition, Cr, V, Mo and Cu elements was added to these melts and the mechanical properties of these specimens were also examined. As a result, the degree of normality (RG) was high in the high carbon contents with low silicon contents region, RG was 143. On the other hand, the relative hardness (RH) was low in the low carbon contents with high silicon contents region, RH was 0.8. The tensile strength was increased with increasing Cr, V and Mo addition except in the Cu element. High strength gray cast iron (upto 470 MPa in tensile strength) can be obtained by Mo addition combining with rare earth elements and manganese.

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  Gas and tar generated from self-curing molds bonded with organic binders such as furan or urethane resins during casting were analyzed qualitatively by gas chromatography. It was shown that gases from all tested molds contain formaldehyde, acetaldehyde and benzene, and that gas from urethane molds contains styrene monomer. The tars generated from furan molds and urethane molds seem to contain benzo [a] pyrene and tar from the urethane mold seems to contain naphthylamine and biphenylamine.
  These compounds were listed as carcinogenic substances by the Japan Industrial Hygienics Society in 1991, it is necessary to take enough care of the physical effects of the above mold.

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  The request for developing more sophisticated properties of Spheroidal Graphite Cast Iron resistant to high temperature are growing storonger year by year. There has however been no dramatic change in measures for decades under which cast iron with a high Si contents would be used as the material resistant to oxidation at high temperatures. For years Mo has thus played a major role as an additive for the purpose of improving strength at high temperatures. In previous work, oxidation resistant properties at high temperature were studied by using the high Si contents (4.0%) S. G. cast iron specimens (test pieces) with co-composition of 0.6%Ni, 0.2%Cr, and 0.5%Cu. 0.2%Cr of molten iron of added solely showed the best improvement in all the data investigated throughout our fundamental experiments. The effects of Si, Cr and RE were studied as additives for improving resistant properties against high temperature in this work, while co-composition was also studied to meet demands for the development of high quality S. G. Cast Iron.

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