Forming and spring-back simulation of CF-PEEK tape preforms

The strive for high energy efficiency through lightweight design, especially for medium- and long haul aircrafts, has significantly increased the use of carbon fiber-reinforced plastics (CFRP) in the aviation industry in recent years [1]. High specific strength, corrosion resistance and improved fatigue life are only a few advantages that qualify CFRPs as structural parts in aircrafts. However, high material, manufacturing and assembly costs are still restricting their use [2]. Highly automated manufacturing processes, which provide a high degree of mounting part integration are needed to lower the part and assembly costs. Structural frames in aircraft fuselages currently make use of a differential design and consist either of aluminum, which provides insufficient specific strength or carbon fiber-reinforced thermosets, which involve long processing times. To overcome these drawbacks, a carbon fiber-reinforced, thermoplastic frame with integrated mounting parts has been developed in order to reduce the complexity of the assembly process. The frame is manufactured in an one-shot process involving tape preform production by automated tape laying (ATL) and a subsequent thermoforming step. ATL allows near-net-shape manufacturing of preforms, which reduces scrap rates to a minimum [3]. The subsequent thermoforming step enables the production of complex 3D-parts with low cycle time [4].