Developing A Hybrid PAEK Overmolded Thermoplastic Composite Bracket

There is a growing interest in the use of thermoplastic composite materials within the aerospace industry because parts can be manufactured faster at lower cost and weight. Developments in high performance thermoplastics are enabling emerging technologies, such as composite overmolding, to widen even further the opportunities for high production throughput and design flexibility, while retaining excellent mechanical properties by combining continuous fiber structures with short fiber reinforced overmolded features. In particular, one variant of a Polyaryletherketone (PAEK) is enabling direct overmolding of Polyetheretherketone (PEEK) for this purpose. One area of development in the aerospace industry includes the substitution of selected metallic brackets with thermoplastic composite brackets. The paper outlines the development of a load bearing thermoplastic hybrid bracket to replace a metal aircraft crash bracket. The bracket consists of continuous carbon fiber PAEK laminate inserts which are injection overmolded with a short carbon fiber filled PEEK resin compound. The paper outlines initial design, part manufacture, testing, trouble shooting and redesign. The paper presents simulations of the process and structure, molding parameter development, insert design, describes unexpected issues and resolutions. The composite bracket resulting 1 from this work provides a significant weight saving over the aluminum bracket it replaces.