On the Plastic Research of Bending of Sheet Metal (4th Report)

Abstract

In the first report it was shown that the analysis of sheet metal bending might be based on the tensile stress-strain diagram only, although deformations were very complicated. From this point of view, the second and the third reports dealt theoretically with the plastic bending of sheet metal by V-type punch and die. And in those reports the profiles of sheet metal in early stages were analized. In the present report, the analysis consits of two progressive cases as follows : -(i) The point of contact of punch with sheet metal is being moved from the edge to the inside along the sheet metal. (ii) The sheet metal is pressed between the faces of dies, and comes in contact with the whole surface. The results agree very well with those of the experiments. By these theoretical treatments, we can analize the whole process of bending that effects on the angular springback Δθ.