A Process for Creating Hybrid Composite Structures Using Additive Manufacturing with Dual-curing Thermosets

Download or read book A Process for Creating Hybrid Composite Structures Using Additive Manufacturing with Dual-curing Thermosets written by Alec Redmann and published by . This book was released on 2021 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: As designers and engineers continue to push the boundaries of high-performance design, fiber reinforced plastics (FRP) are increasingly finding use in structural applications due to their light weight and superior mechanical properties. Many applications, especially in the aerospace and automotive industries, require geometrically complex designs with multiple components and materials assembled during manufacturing - typically using mechanical fasteners or adhesives. Adhesive bonding is the generally preferred technique when manufacturing FRP structures for a multitude of reasons: adhesive bonding does not require material removal, reducing stress concentrations and stress cracking introduced by drilling; galvanic corrosion is minimized, which can be responsible for significant maintenance costs; and the weight penalty of mechanical fasteners is avoided. Despite these benefits, adhesive joining is often avoided due to quality control concerns and the need for special fixtures and surface treatments.In order to solve these problems, a new process has been developed for joining composite members utilizing additive manufacturing and a dual-curing resin system. The resin is first 3D printed using a UV process; resulting in a semi-rigid, but only partially cured part. This part still has chemical potential and bonding availability when it is integrated with pre-impregnated fiber reinforcement. The assembly is then heated to activate a second curing reaction that co-cures the two materials, resulting in a permanent, void-free bond. Due to the co-curing nature of this new joining process, there is no longer a need for surface treatments or additional fixtures. Furthermore, these adhesive parts can utilize the design freedom of 3D printing by including intricate internal structures or customized features to improve assembly. The combination of 3D printed joining elements and FRP enables a new family of hybrid, high-performance composite structures.