To solve the problem that casting parts, which are cast with a laminar flow die-casting in order to prevent the entrapment of a gas and can not be used for the portion (the weakest cross sectional part) which concentrates the stress in important preserved parts, such as an under carriage member of a car, since an abnormal structures, such as a broken chill part, a component segregation, an acicular crystal, an oxide, becoming the primary generating point of crack in the casting, are developed or easily grown.

The vibration in the molten metal (M) is applied to the molten metal (M) supplied into a plunger sleeve 15 from the three directions at a rod 19 side, a shunt circuit 21 side and the lower side of a side surfaces of the plunger sleeve 15, and the development or the growth of the acicular crystal and the primary crystal of the broken chill part are restrained or finely spheroidized and the oxide is crushed or the development of the component segregation and shrinkage hole are restrained or eliminated by stirring effect of the molten metal (M) and the ultrasonic cavitation effect with the ultrasonic sound flow developed at the front part of the vibration end.