The further development of in-mold-assembly (IMA) technologies for structural hybrid components is of great importance for increasing the economic efficiency and thus the application potential. This paper presents an innovative IMA process concept for the manufacturing of bending loaded hybrid components consisting of two outer metal belts and an inner core structure made of glass mat reinforced thermoplastic (GMT). In this process, the core structure, which is provided with stiffening ribs and functional elements, is formed and joined to two metal belts in one single step. For experimental validation of the concept, the development of a prototypic molding tool and the manufacturing of hybrid beams including process parameters are described. Three-point bending tests and optical measurement technologies are used to characterize the failure behavior and mechanical properties of the produced hybrid beams. It was found that the innovative IMA process enables the manufacturing of hybrid components with high energy absorption and low weight in one step. The mass-specific energy absorption is increased by 693 % compared to pure GMT beams.

The main work issue is to optimize the manufacturing of hybrid profiles bearing loads defined by the automotive application, based on the monitoring of the production quality using computed tomography (CT). This offers an efficient, accurate and non-destructive inspection of the products in terms of time and costs in order to prove the production quality. The investigated parts consisted of glass mat reinforced thermoplastic (GMT) 3D structures covered by aluminum straps (AA5754) with different thicknesses. They were manufactured at varied process temperatures by compression molding. The profiles quality was evaluated by CT, where the designed and actual dimensions were compared and the porosity and the fiber distribution inside the profiles were examined. In a next step, quasi-static three point bending tests were carried out on the produced profiles in order to evaluate the impact of the production effects on the mechanical behavior. First CT results showed an inhomogeneous distribution of the fibers in the matrix especially for the profiles fabricated at lower tool temperature. Pores were also found in the areas with low concentration of fibers. After bending, the cracks tended to propagate along the fiber orientation. Consequently, the main failure mechanisms consisted in inter fiber fracture and delamination of the aluminum strap.