Patent ID: 9003857
Filing Date: 2015-04-14
Classification: B21D,C21D,Y10T

Abstract:
1. A press-forming method comprising: shaping a plate to include a first portion having a first width, a second portion having a second width greater than the first width, a trapezoidal portion that connects the first portion and the second portion, and a current density changing portion at a corner of the first portion that is adjacent to the trapezoidal portion; performing a heating process of forming the plate into a final predetermined shape by pressing and cooling the plate after the heating process, wherein shaping the plate includes: wherein a current density of the current density changing portion is different than a current density at other portions of the plate while the current is passing through the plate to provide a temperature distribution in the plate that is controlled such that the plate is not heated uniformly prior to the forming of the plate, and wherein decreasing the inclination angle for the edge of the trapezoidal portion widens and increases the area of the region of the plate that is heated to the quenchable temperature.