In this paper, the power assisted wire suspension system which supports the setting of a mold is presented. The purpose of this system is to eliminate the engineer's burden and to support the operation for beginners. This system measures the swing angle of the rope and the .uctuation of the mold's weight caused by the operator's force, and it moves the AC servo motors of both the horizontal and vertical axes in accordance with the detected swing angle and force respectively. The e.ectiveness of this power assisted system is con.rmed by experiments for mold setting.

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  The purpose of this study is to clarify the continuous cooling transformation behavior and the heat treatment characteristics of five (5) kinds of low alloyed ductile cast irons containing Mo between 0mass% and 2mass%. The specimens were austenitized at 1223K-900s, and the range of cooling time from Ac₃ to 773K was about 3 to 4000s.
  Ferrite, pearlite, bainite and martensite transformation regions existed in CCT diagrams for ductile cast irons used. The ferrite transformation region in the CCT diagram shifted to a longer cooling time side with an increase in Mo content because of the impurity solute drag effect of Mo. The pearlite transformation region in CCT diagrams for ductile cast irons also shifted to a longer cooling time side. Movement to the long time side of this pearlite transformation region is considered owing to the behavior that Mo suppresses the growing speed of pearlite. The bainite transformation region existed even at a longer cooling time side in CCT diagrams when Mo was added. However, critical cooling time and transformation temperature for bainite in ductile cast iron containing Mo remained about the same, which would have originated from the decrease in the amount of ferrite and pearlite by Mo as well as the promoting action of the bainite transformation by Mo. The martensite transformation region existed even in the longer cooling time range with increasing Mo content. The Ms temperature of low alloyed ductile cast irons was not influenced by Mo, but the quenching hardness of 0Mo cast iron was 630HV10, and that of 2Mo cast iron was 700HV10. The difference in hardness is thought to have originated from the crystallized and precipitated carbide content.
  In conclusion, Mo has little effect on the hardenability for low alloyed ductile cast irons.

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  Die casting is adequate for mass production and has the advantage of being able to yield complicated shapes accurately. One defect of die casting for high-speed injection molding, however, is the occurrence of air entrapment. To avoid air entrapment, velocity control of the plunger has proved to be very effective. In this paper, fluid behavior and the quantity of air entrapment caused by a die casting plunger movement are analyzed using CFD. The optimum velocity control input of die casting plunger is calculated in order to reduce and prevent air entrapment in die casting products. Optimization is performed by a genetic algorithm incorporating the CFD simulator.

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