Abstract
In this study, it was investigated by comparing the experimental hemming by the 3 steps and 2 steps in order to stabilize the quality of the hemming process. In the experimental results, the three-step hemming superior to the two-step one and the dimensional stability of part that was made by the three-step on was high. When the second stage Hemming has been found that the deflection caused by the force to the wear of the punch becomes larger plane can be folded by the hemming crimping and crimp uncertain.