METHOD FOR MANUFACTURING OF QUENCHED STEEL SHEET, PRESS MOLD USED IN THE METHOD

摘要

PURPOSE: A manufacturing method of a thermal process curing steel sheet and a press mold which is applied in the same method are provided to improve workability by applying different cooling speed according to the processing amount. CONSTITUTION: A steel material is mold pressured by using a top and bottom mold. The cooling speed is differently set according to the processing amount(A). A plurality of cooling lines is formed on the top and bottom mold(b). The mixed-refrigerant of the oil and water is provided to a plurality of cooling lines(C). The tensile strength of the small processing amount part is 1400~1500MPa. The tensile strength of the large processing amount part is 1200~1400MPa.