Validation of experimental analysis of the PC thermoformed product using finite element methods

Thermoforming process has now become the most suitable and conventional method for manufacturing 3D circuits with complex geometries. The mold of commercially available automobile lighting LED is developed using CNC machine. The stretchable circuit is printed on a thermoplastic substrate through screen printing technique before undergoing thermoforming process. The factors that affect a thermoformed product are the stretch level and thickness reductions of the substrate. This paper aims to study the effect of the variation in dimensions of the thermoformed product without the printed stretchable circuit on the substrate. Finite element methods (FEM) analysis is also carried out in order to visualize the behavior of the substrate in terms of area stretch ratios (ASR) and thickness reductions of different wall surfaces after deformation according to the geometry of the mold. The ASR and thickness values obtained by experiment and simulation are compared. As a result, the simulated values are bit higher than the experimental ones but they are acceptable, therefore, the behavior of thermoforming product like large stretch areas and less thickness, can be determined prior to the actual thermoforming process of the product with printed stretchable circuit.