VERTICAL TYPE CONTINUOUS CASTING METHOD OF ALUMINUM ALLOY SLAB

摘要

PROBLEM TO BE SOLVED: To provide a vertical type continuous casting method of an aluminum alloy which can cast a large rectangular cross sectional slab of (>=300mm thickness×>=1000mm width) without crack in a cast slab. SOLUTION: This method is the one which the molten aluminum alloy M is introduced from the upper part of a vertical opening type forcedly cooling mold 1 and solidified shell is formed by primary-cooling with the mold and the cast slab S forming the solidified shell is drawn out from the lower part of the forcedly cooling mold, and coolant medium fluid is directly thrown onto the cast slab surface as the secondary-cooling to cast the aluminum alloy slab having the large rectangular cross section of >=300mm thickness×>=1000mm width. In this case, cooling capacity at both side positions having 1/3-1/4 length in the width direction of the wide surface part from the center position to the corner parts of the wide surface part 3 of the mold is set at 0.8-1.5 times to the cooling capacity of the center part of the wide surface part to execute the primary-cooling with the mold. Further, the coolant fluid quantity in the secondary-cooling means is set to 1/4-3/4 of that in the primary-cooling means.