Extensive numerical simulations of MPSF processes have been performed by dynamic explicit finite element methods, and the multi-point stretch forming processes for the parts of different shapes using different MPSDs and different elastic cushions are investigated. A series of numerical results are obtained, these results reveal the effects of the size of the punch element and the shape of the MPSD on the sheet metal deformation and the role played by the elastic cushion. The main points are concluded as follows: (1) Since the punch elements present concentrated loads to sheet, the sheet will be dimpled by the tip of punch element in a MPSF without elastic cushion. To obtain qualified part, elastic cushion have to be used in multi-point stretch forming of sheet metal. (2) To suppress dimple effectively, a thick elastic cushion should be employed in MPSF. But a thicker elastic cushion may make more discrepancy between the formed part and that of MPSD. In MPSF operation, the thickness of elastic cushion must be chosen reasonably, and in MPSD shape design, the influence of elastic cushion should be taken into account. For the case investigated in this paper, an elastic cushion with thickness 10 mm is suitable for the MPSF process. (3) The smaller the size of punch element is (or in other words, the more the number of punch element is in a MPSD), the better the obtained MPSF result will be. Since a small punch element will make the MPSD complicated and expensive, and the size of the punch element should be designed carefully in practice. For the case investigated in this work, a punch element smaller than 12 mm x 12 mm is a reasonable selection. (4) The smaller the curvature of the part shape is, the better the obtained MPSF result will be. In the central region of MPSD the shape errors are small, but in the region near the edges of MPSD, the shape errors is large, sometimes maybe quite large. This point should be noted in the application of MPSF.
Numerical simulation for the multi-point stretch forming process of sheet metal
Journal of Materials Processing Technology ; 209 , 1 ; 396-407
2009
12 Seiten, 18 Bilder, 4 Tabellen, 26 Quellen
Article (Journal)
English
Numerical Simulation for Process of Multi-Point Stretch Forming with Flexible Clamp Mode
British Library Online Contents | 2008
|Stretch forming of sheet metal
Tema Archive | 1989
|Simulation validation of advanced sheet metal under stretch forming
Automotive engineering | 2006
|Multi-Point Stretch Forming Experiment and Numerical Simulation of Saddle Part with Flexible Clamp
British Library Online Contents | 2012
|Numerical Simulation of Multi-Roll Stretch Forming Process with Different Lubrication and Rollers
British Library Conference Proceedings | 2012
|