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Effect of Die Cooling Time on Component Mechanical Properties in a Front Pillar Hot Stamping Process

곡선형 냉각채널 금형을 사용한 프론트 필라 핫스탬핑 공정에서 금형냉각시간이 기계적 특성에 미치는 영향

  • Received : 2019.04.10
  • Accepted : 2019.05.17
  • Published : 2019.06.30

Abstract

Researchers have recently begun to study hot stamping processes to shorten the mold cooling time and improve productivity. These publications explain that the mold cooling time can be reduced by using a curved cooling channel, where the mold surface is processed to a uniform depth, instead of a straight cooling channel that uses the conventional gun drilling machine. This study investigates the characteristics of the front pillar of an automobile after using a mold with a curved cooling channel. To analyze the change in properties, we used a 1.6 mm boron steel blank and heated the prototype at $930^{\circ}C$ for 5 minutes. Next, we formed the prototype with a load of about 500 tons while varying the mold cooling time between 1 and 10 seconds. We subjected each prototype specimen to a tensile strength test, a hardness test, and a tissue surface observation.

Keywords

References

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