A New Sheet Metal Forming Technique Using Developed Blanks Combined with Joining Process

本研究开发了一种将拉深成形与连接成形相结合的超深杯形件成形新工艺。为了减小坯料的拉深阻力，采用了将凸缘部分分割成花瓣状单元的展开坯料代替传统的圆形坯料。这使得在一次拉延操作中生产出非常深的杯状物成为可能。然而，拉延杯状物的侧壁处的瓣状物之间仍然存在接缝，这些接缝仅是接触，而不是接合。为了在一次拉伸操作中从开发的坯杯生产无缝杯，在深拉伸过程中将壁侧的瓣状物机械接合。研究了两种机械连接方法：第一种方法是利用翼缘处的坯料搭接进行机械连接。另一种是通过卷曲花瓣和啮合在一起进行机械连接。并对胶接和普通焊接方法进行了试验研究。阐明了每种焊接工艺的连接或焊接条件对焊缝性能的影响。作为一种替代有用的焊接方法，超声波焊接的可能性也进行了研究。

In this research, a new metal forming technique for production of very deep cups was developed, in which deep drawing method was combined with joining process. In order to reduce the drawing resistance of blank material, the developed blank, the flange portion of which is divided into some elements just like petals, is employed instead of a conventional circular blank. This makes it possible to produce a very deep cup in one drawing operation.However, there remain seams between petals at the side wall of drawn cup, which are only contacted, not jointed. To produce a seamless cup from the developed blank cup in one drawing operation, petals at the wall side were jointed mechanically in deep drawing process. Two mechanical jointing procedures were examined: In first method, the overlap of blank at flange were utilized for jointing petals mechanically. Another mechanical joint was conducted by curling petals and meshing together. Adhesive joint and ordinary welding method were also attempted experimentally. The effects of the jointing or welding conditions on properties at seams were clarified about each jointing process. As an alternative useful welding method, the possibility of ultrasonic welding was also investigated.