Abstract: The characters of flexible discrete clamp stretch forming (DCSF) machine were introduced. A FE model of flexible DCSF was built. Spherical surface and saddle surface were selected for simulation. The influences of stretching velocity, friction coefficient and clamp shape on the forming results were researched. The numerical simulation results showed that the stretching velocity 1 m/s is good for satisfactory forming efficiency and accuracy. The better the lubrication condition is, the more homogenous distributions the stress, strain and thickness are. The clamp shape is sensitive to liquidity of transitional area and clamping area, more uniform strain and smaller thinning value were got by circular clamp. The simulated results are validated by experiment. The obtained achievements are useful for the optimal design of DCSF machine and the practical stretch forming process implementation of sheet metal.

Key words: materials synthesis and processing technology, sheet forming, flexible stretch forming process, discrete clamp