PURPOSE: To obtain sufficient cooling effect by using a mold arranging layer of metal material having m.p. lower than the finish phase transition temp. during solidifying process of an alloy material or layer with this metal material mixed with sand at outer circumference of a sand mold.

CONSTITUTION: At the time of casting the alloy material by using the mold to manufacture a metallic mold, the mold arranging the layer of metal material having m.p. lower than the finish phase transition temp. by 10°C during solidifying process of the alloy material or the layer with this metal material mixed with the sand at the outer circumference of sand mold, is used. During solidifying process of the alloy material, the sufficient cooling effect is obtd. with melting latent heat in the metal material. By this method, solidifying velocity of the alloy material is quickened and the phase transition is progressed in a short time and phase separation caused by difference of sp. gr. between component is not developed, and further, coarsening of crystal with slow crystallizing velocity by generating the heat caused by the phase transition, can be prevented.