Homogenized FEA of Composite Sheet Materials for Improved Thermoforming Process

Absence of reliable analytical tools to model thermoforming of automobile headliners leads to lack of understanding of critical relationships between design, material and process, resulting in large proportions of scraps and in some cases, over engineering. Thus, a Finite Element Analysis (FEA) of thermoforming of a composite sheet material has been formulated and implemented. An homogenization approach is suggested, in which the layered composite is treated to behave as a single material. By mapping key process variables into analysis, a simulation has been successfully carried out on a headliner prototype development tool. Results obtained with such development tool show good correlation to key headliner defects such as wrinkles and failures.