Parameter identification of GTN damage model using response surface methodology for single point incremental sheet forming of IF steel

Abstract

ABSTRACT The single point incremental sheet forming (SPIF) is an advanced sheet metal forming technique, also known as dieless sheet forming. Formability in incremental sheet forming is defined by the maximum formable wall angle or the depth of forming. In this work, the formability in SPIF is predicted by the Gurson-Tvergaard-Needleman (GTN) model. The parameters of the GTN model was optimised by the response surface methodology (RSM). These parameters were determined by the tensile test experiment and simulation correlation. The optimised parameters were used in the numerical analysis of SPIF process to predict the failure. The results are in good agreement with experimental results and model predicts depth of forming with acceptable accuracy. Further, as the wall angle of the component increases the formability decreases in SPIF, which is well predicted by the numerical model with optimised parameters. In addition to this, the thickness reduction and damage evolution for varying wall angle has been reported with help of numerical analysis.