PURPOSE: To manufacture the aluminium deformed material to be extruded of high accurate shape by extruding the shaped material connected with the imitation part through the temporary connecting part to the thin wall end part in one body, breaking this temporary connecting part, separating the imitation part and removing.
CONSTITUTION: The Al deformed material to be extruded 100 having the thin wall part 102 and the thick wall part 101 is extruded by using the extruding dies. Then, the material 100 to be formed connected integrally with the imitation part 120 through the temporary connecting part 110 to the end part of the thin wall part 102 is extruded. And then, the temporary connecting part 110 of the material 100 to be formed is broken and the imitation part 120 is separated and removed. Therefore, the cooling speed at both end parts of the thin wall parts are made uniform at the cooling time after extruding, so the unevenness or the un-symmetricalness of the distribution of strength caused on the difference of cooling speed can be improved.
TANIGAWA MASAKAZU
MICHISAKA KOUZOU
