2020 Volume 61 Issue 11 Pages 2128-2133
In this work, by focusing on multiprocess tube flaring for eccentric parts, we studied the effect of punch shape on deformation behavior by finite element analysis. In the case of using only the eccentric punch, thickness deviation occurs in the circumferential direction and thickness reduction is suppressed because the tube is greatly expanded at the 180° circumferential position. However, it is found that the thickness deviation and thickness reduction are suppressed by evenly expanding both sides using a concentric punch. Furthermore, although the punch shoulder radius has a negligible effect on formability, it is confirmed that the deformation near the tube edge transitions from uniaxial tension to pure shear as the punch semiangle is increased. The above result clarify that by using concentric punches with punch semiangle larger than the taper angle of the part shape from the initial process, the thickness reduction is drastically minimized compared with other forming methods.
This Paper was Originally Published in Japanese in J. JSTP 60 (2019) 182–186.
