The optimization of single point incremental forming (SPIF) to produce conical cups

Single point incremental forming (SPIF) is an economical and fast sheet metal forming technique, which does not require a set of specified and complicated dies and a press machine. A finite element method (FEM) model of an incremental sheet metal formed conical cup is developed using ABAQUS software. The geometric shape and processing parameters for the punch of the tool path on the thinnest ( T ) and uniformity ( U ) of the sidewall thickness of a finished conical cup are measured by SPIF. The SPIF variables for the experimental design include the punch diameter ( D ), the Z-axis feed-down distance ( Z ), the rotational speed of the punch ( R ) and the feed rate ( F ). The experiment uses 25 sets of analogs and a Box-Behnken design (BBD). Minitab software is used for a regression analysis and to develop the prediction equations for T and U for a finished conical cup. The FEM model and response surface methodology (RSM) are used to determine the optimum design for T and U for a finished conical cup. Compared with the prediction equations for T and U for a finished conical cup that are calculated using RSM, the results for the FEM demonstrate excellent accuracy.