SIMULATION OF METAL-FORMING PROCESSES BY VOLUME-CONSERVED METAMORPHOSIS

In metal forming, metal is deformed under high stress into a desirable shape. The material will crack if stress is applied in an undesirable magnitude and direction. Finite element analysis can definitely be us ed here, but this is a time-consuming process and requires intensive c omputation power. A ''three-dimensional, volume conserved and paramete r controlled'' morphosis algorithm is developed and discussed in the p aper. The algorithm suggests an alternate mean for a coarse deformatio n analysis and is expected to require less computation. The metal form ing process is emulated by morphosis and stress values are evaluated o nly at points with high strain rate. The volume-conserved property pro vides a pre-requisite to emulate the metal forming process. The deform ation trend is then controlled roughly by parameters, so as to provide a better emulation of the forming process. Most popular algorithms us ed in morphosis rely on the interpolation of corresponding point-pairs , and they are not quite applicable here due to the difficulty in volu me control. The proposed algorithm is to first transform the objects b efore and after the deformation into another domain, which provides a good control of the volume information. Interpolation in the new domai n is then carried out. An inverse-transform is then performed to obtai n the intermediate shapes in the deformation. The representation of th e solid in the new domain is, in fact, a new solid modelling scheme th at emphasizes the volume-conservation property of the modelled solid. Efficient transformation between the new scheme and the conventional r epresentation to make the morphosis possible is also discussed.