Development of a Combined Process of Organic Sheet forming and GMT Compression Molding

This research describes the development of a combined one-step process of complex organic sheet forming and GMT (Glass Mat Thermoplastics) compression molding which can be integrated in processes using conventional stamping technology. Hence, no additional injection molding step is required. Compression molding allows adding a third dimension to the two-dimensional organic sheet. Thus, reinforcements or screw connection points can be produced out of complex 3D-structures with fiber lengths up to 40 mm. While forming simulations for both separate processes already exist to a certain degree of maturity, the coupling of organic sheet forming and GMT compression molding in one software tool involves major challenges. This paper presents a solution approach that depicts the combined process in a single FE-based forming simulation carried out with LS Dyna. The investigation was mainly focused on the interaction between the two materials and the temperature distribution which largely influences the forming effects and the bonding of the materials to one another.