PURPOSE: To form a defectless aluminum alloy casting free from fine defects and to greatly improve the mechanical properties of the produced aluminum alloy casting.
CONSTITUTION: A lost foam pattern 1 is installed into aluminum and aluminum alloy grains 2 having good thermal conductivity and the melt of the aluminum alloy is poured into this lost foam pattern 1. The lost foam pattern 1 is burned by the melt of the aluminum alloy and the lost foam pattern 1 is substd. with the poured melt to start solidification. The melt of the aluminum alloy is filled in the lost foam pattern 1 and the heat is rapidly transmitted by the aluminum and aluminum alloy grains 2 which have the good thermal conductivity and are in contact with the melt of the aluminum alloy at this time. The solidification of the poured aluminum alloy is thus rapidly progressed and the cooling rate at the time of the solidification and the cooling rate after the solidification are greatly increased. The defectless aluminum alloy casting free from the fine defects is, therefore, formed and the mechanical properties of the produced aluminum alloy casting are greatly improved.
SAITO MASAHIRO
KANDA KAZUHISA
