Hydro-multipoint forming, a challenge in sheet metal forming

Abstract

The Hydro-Multipoint Forming is a new technology for sheet metal manufacturing appeared as a response to the demands of the global marketplace toward batch and customized production. The technology is a combination between two metal forming processes multipoint forming and hydroforming. The Hydro-Multipoint Forming reconfigurability is assured mainly by the flexible surface of deformation, generated by the axial moving of a number of pins, from the pins network. Using the hydraulic pressure the necessary force to deform the material along the reconfigurable surface of deformation is obtained. In the paper the elements of the new Hydro-Multipoint Forming technology are presented. A simulation model is developed. The model is created using FEM, and both the interpolator associated with the pressure chamber and the interpolator between the pins and the blank are considered. The process of deformation is analyzed in terms of strains, stresses and prevalent defects, respectively dimpling and wrinkling. Using an experimental tool for Hydro-Multipoint Forming the material deformation is analyzed considering the geometrical variations. Finally, a discussion of the numerical and experimental results is made and limits and possibilities for future process improvements are highlighted.