Study on the Choice of a Suitable Material Model for the Numerical Simulation of the Incremental Forming Process of Polymeric Materials

The aim of this paper is to identify the most suitable material model for the numerical simulation of the incremental forming of polymeric materials using the finite element method. The analysis program used was Ls-Dyna, and two material models, namely material 24 (Piecewise Linear Plasticity) and material 89 (Plasticity Polymer), were chosen for comparison from the library of the program. A comparison was made between two polymeric materials, polyamide PA 6.6 and polyethylene HDPE 1000, with the following dimensions of the forming tools: punch diameter, Dp = 6 mm; die length, Ld = 190 mm; die radius, Rd = 5 mm; die corner radius, Rcorner = 10 mm; and blankholder length, Lbl = 190 mm. The simulation using the finite element method was performed with the Ls-Dyna software, and the experimental research was carried out using the Kuka KR210-2 robot. The strains were measured with the Aramis 2M optical system. Experimental investigations were carried out simultaneously, and the results obtained were compared in terms of main strains, thickness reduction, and forces on three directions. Close results were obtained between theoretical and experimental research for both material models.