알루미늄 판재의 성형성 향상을 위한적외선 국부 열처리법의 곡선형태 적용에 관한 연구

Abstract

Auto industries have tried to employ lightweight alloys to improve the fuel efficiency of manufactured vehicles, as the environmental concern becomes an important issue. Even though the aluminum alloy is one of the most appropriate lightweight alloys for auto parts, the low formability of an aluminum alloy has been an obstacle to its application. In order to resolve the low formability problem, a recent study (Lee et al., 2017 [1]) showed that the infrared (IR) local heat treatment can improve the formability with a reduction of heating energy. However, the aforementioned study was limited to only a linear line heating. Since many of the available auto parts as applicable to vehicle manufacturing have a curved line shape, the heating experiments for a curved line should be studied. The possibility of building IR lamps having complex shapes is an advantage of the IR lamp, since it can control the heating shape. This work conducted the IR local heat treatment for the curved line. The experimental results show that the IR local heat treatment can improve the formability of the aluminum alloy for curved line. Additionally, it is shown that the IR local heat treatment also reduces the heating energy when it is compared with the furnace heating which heats a blank as a whole. A numerical simulation with a stress-based forming limit diagram also supports the experimental results