Research on Double Curved Forming of Sheet Metals Lacking Workability and Bending of Profile Sections

为了使本课题组独创的喷丸成形实用化，新研制了鼓风机喷丸成形装置，取得了以下成果：1.指出了扫掠式喷丸的最大有效喷丸能的存在。1.确定了材料性能的成形性差异是由于加工硬化特性的差异。1.在板材弯曲中，提出了通过检测工作板材的投影长度来将弯曲角度确定为所需值的新思想。通过对侧喷丸，完全抑制了喷丸边缘出现的下垂。1.通过对带有透镜形孔的掩模覆盖的旋转工作段进行喷丸处理，并向相反的方向弯曲，实现了半圆形截面的弯曲，即通过从对侧对带有双曲线孔洞的掩模覆盖的工作段进行喷丸，实现了马鞍形的成形。1.通过从对侧对带有双曲线形孔的掩模覆盖的弯板进行喷丸，实现了对应于双曲线弯曲的鞍背形状的形成，抑制了边缘的下垂。

In order to make peen forming which was developed originally by this investigator possible to apply practically, blower type peen forming apparatus was newly set up and following results were obtained.1.The existence of the maximum effective peening energy in sweeping type peening was pointed out.1.It was confirmed that the difference in formability concerning material properties was caused by the difference in work-hardening characteristics.1.In bending of a sheet, a new idea to settle a bending angle to a desired value by sensing the projected length of working sheet was proposed, and the usefulness was confirmed.1.The droop which was appeared at the peened edge was completely suppressed by peening from the opposite side.1.Bending of a semi-circular section was achieved by peening the rotating work section covered by mask with lens type hole, and bending to the oppesite direction, that is saddleback shape forming was achieved by peening the one covered by a mask with hyperbolic curve hole from opposite side.1.Saddleback shape forming correspond to double curved bending was achieved by peening the bent sheet covered by a mask with hyperbolic curve type hole from opposite side and the droop of the edge was suppressed by the above mentioned way.