Process analysis based on experimental tests and numerical modelling of single point incremental forming of sheet metal: effect of the principal process parameters

Incremental sheet forming (ISF) is a very promising technology to manufacture sheet metal products by the CNC controlled movement of a simple forming tool. It is considered as an innovative and flexible sheet metal forming technology for small batch production and prototyping, which does not require any dedicated die or punch to form a complex shape. Although incremental sheet forming is a slow process, the cost reduction linked to the fact that punches or dies are avoided, makes it a very suitable process for low series production, in comparison with the traditional stamping or drawing processes. This paper investigates the process of single point incremental forming of aluminum truncated cones and square pyramids geometries both experimentally and numerically. Concerning the numerical simulation, the finite element models are established to simulate the process by using a static implicit finite element code ABAQUS/Standard. In this article, the reported approaches were mainly focused on the influence of some crucial computational parameters. The influence of several parameters will be discussed: the initial sheet thickness and the workpiece geometry. The output of the simulation is given in terms of the punch forces evolution generated in this forming process and the final geometry. A comparison between the simulation results and the experimental data is made to assess the suitability of the numerical models. Experimental and numerical results obtained allow having a better knowledge of mechanical responses from different parts manufactured by SPIF with the aim to improve their accuracy. Predicted results show good agreement with experimental data for these geometries of the cones and pyramids. It is also concluded that the numerical simulation might be exploited for optimization of the incremental forming process of sheet metal