Direct writing of continuous carbon fibers/epoxy thermoset composites with high-strength and low energy-consumption

Epoxy resin-based thermoset composites are extensively used in industries with billions of dollars revenue every year. High-rate manufacturing process is highly sought-after to produce complex composite structures geometric flexibility and low energy-consumption. This work demonstrates printing in-situ cure epoxy thermosets via self-sustaining frontal propagation. Specifically, latent initiator the resin formulation was tuned from 2 mol% 0.05 lower propagation temperature ~290 °C ~240 without decreasing reaction rate. The soaked into continuous carbon fiber (CF) tows then printed through a modified direct ink writing system. Synchronization curing resulted CF/thermoset (c-CFTC). Both single dual nozzle print-heads were print c-CFTC tunable volume fractions. As-printed specimens exhibited exceptional tensile strength, 1.15 GPa at 48 vol% fibers 0.42 18 direction ~35.5 MPa transverse direction. energy consumption also calculated, indicating 3.6 billion kilowatt-hours (kWh)/year energy-saving comparison conventional processes hours high-temperature oven curing, equivalent 360,000 US families per year (single family electric consumption: 10,000 kWh/year). speed 7.5–13.8 cm/min dependent on fraction, thus production rate estimated be 400–800 cm3/hour. Such high-rate approach could revolutionize industry aerospace, automobile, marine environmental sustainability.