Investigation on a Microextrusion Process of Parallel Protrusions from Metal Strip

Abstract

The continuous purchase of higher quality standards in the production with parallel reduction of the costs leads to the need of a robust process design avoiding as much as possible the occurrence of defects in the production. Complex processes like microforming are highly dependent on local raw material changes, normally affecting more than 10% of the production which, as a result, has to be rejected. A possible approach consists in an adaptive control system based on a metamodel processing the data of online measuring: in a multistep microforming process the relevant features of the workpiece are measured inline and the deviations reduced by online adjustment of the most effective process parameters. This paper presents a simulative study of a full forward extrusion process from metal strip. Multiple parallel ribs are formed in the middle of a more complex workpiece resulting from a multi step microforming process made up also of cut-ting, deep drawing and bending stages. The simulations are based on a full factorial design of experiment which reproduces the different workpiece conditions, mainly due to strip thickness spread and variable lubrication.