In-space manufacturing of thermoset composite structures: A short review

In-space manufacturing (ISM) enables on-demand fabrication of large space structures that exceed current launch payload volume. While past research has focused on additive manufacturing of thermoplastics and their composites, fiber-reinforced thermoset composites (FRTSC) offer lower energy processing, superior thermomechanical properties, durability, and easy integration of multifunctional material systems through diverse chemistry, composite architecture, and novel processing. The challenges to using thermosets composites in space are containment of fluids, control of the chemical reaction with compact processing equipment, and maturation of processing methods. Recent studies suggest that in-space manufacturing of FRTSC can be advanced using encapsulated catalyzed poly(dicyclopentadiene) (pDCPD) carbon fiber preforms. Structural elements can be processed with modest equipment using frontal polymerization (FP) of pultruded composite tubes, bulk polymerization of solid beams by rapid out-of-oven lamination (ROL), and FP of panels with programmed curvature from flat additively manufactured preforms. Looking ahead, novel chemistry, integrated devices, and in-space manufacturing of FRTSC can be combined to achieve multifunctional space structures with self-healing, self-passivation, and self-sensing and extend the service life of space structures. This review examines the current state of ISM, current challenges, and the emerging role that ISM of multifunctional thermoset composites can have in enabling sustainable space infrastructure.