PRODUCTION OF ALUMINUM OR ALUMINUM ALLOY CAST BLOCK

PROBLEM TO BE SOLVED: To provide a producing method of an aluminum or aluminum alloy cast block which can prevent the leakage of molten metal and the crack on the bottom part of the cast ingot developing a gap between a mold and the cast block. SOLUTION: After arranging by inserting a bottom base 2 into the lower end opening part of a cylindrical mold 1, the molten aluminum or aluminum alloy 10 is poured into the mold 1 and after forming the solidified shell 13, while pouring the molten metal into the mold, the bottom base is lowered and the cast block is continuously drawn out to produce the cast block. In such a case, at the time of starting the casting, heat conductive depressants 11, 12 of two or more kinds which are different to the heat conductive depressing effect, are successively arranged in the casting direction, and after starting the casting, the heat conductive depressants are drawn out together with the cast block from the mold. The heat conductive depressants 11, 12 are arranged to the center part in the width direction of the inner wall of the long wall sides of the mold 1 with the length having >=1/2 of the width size and the total length of the heat conductive depressants in the cast direction is 60-150 mm. As this heat conductive depressant 11, e.g. an aluminum foil is used and as this heat conductive depressant 12, e.g. a glass fiber cloth is used.