Investigations On Peen Forming (2nd Report; On The Forming Mechanism)

Author:  Kondo, Tsuzuki, Kato
Source:  Conf Proc: ICSP-1, (p.565-572)
Doc ID:  1981040
Year of Publication:  1981
Abstract:  
Mechanisms of bulging or sinking deformation of sheet metals in peen forming are basically investigated by using a two dimensional model of a roller tool depression against a rectangular plate specimen and the change of the forming mode is explained from the change of the planar strain distribution to the thickness direction. Detail experiments reveal that there are four types of the deformation process according to working conditions in bulging of a disc, that is, a monotonous bulging, a monotonous sinking, a bulging accompanying temporary sinking and a sinking accompanying temporary bulging. The reason for these differences of the deformation type are clarified from the effect of the bending moment by the restriction of the flange portion material. Effects of the shot size in the range from 0.4 mm to 8 mm in diameter on the forming efficiency and the surface quality of the products are investigated and the optimum working conditions are clarified. Descriptors: Bulging mechanism; Roller indentation model; Deformation type; Flange restriction; Optimum working conditions; Forming efficiency; Surface quality