METHOD FOR MANUFACTURING LAYERED HOT STAMPING MOLDED BODY AND LAYERED HOT STAMPING MOLDED BODY

摘要

[Problem] To solve a problem related to the bending of a steel sheet caused by a difference in a temperature increase rate between a layered part and a sheet part. [Solution] The present manufacturing method comprises: a step for heating a layered blank; a step for transporting the heated layered blank; and a step for pressing the heated layered blank into a mold. In the heating step, when the thicknesses of first and second steel plates are set as t1 and t2, and average heating rates at a plate temperature between 20 °C to 800 °C in a portion of the total plate thickness (t1+t2) of the layered part and a portion of a non-layered part are set as V and v1, the total plate thickness (t1+t2) is 2.5-5.0 mm, and the maximum length L of the layered part is 100-1100 mm. An area S1 of the first steel plate, an area S2 of a portion of the second steel plate overlapping the first steel plate, and the average heating rates V1, v1 satisfy expressions (1) to (3), and heating is performed at a heating temperature and a heating time within a specific range in a coordinate plane defined by the heating time and the heating temperature.