Using Electric Fields for in Situ Curing of Carbon Fiber/Phenolic Composites in Additive Manufacturing

In this paper, we demonstrate electrothermal heating and curing of carbon fiber (CF)/phenolic composites to enable successive deposition for additive manufacturing (aka 3D printing). Electric fields are capable of heating susceptor materials, which makes them a potential heat source for 3D printing thermoset composites, such as CF/Phenolic prepregs. We investigated the heating response of CF/phenolic prepregs when exposed to electric fields and found that our prepregs reached the target temperature of 210 °C when the electric field applicator was supplied with low power (8 W). We also show continuous heating and curing by translating prepregs through an electric field. Finally, we demonstrate additive manufacturing by manually depositing a layer or prepreg, using an electric field to perform in situ curing, and then repeating the process to create multilayer structures. This multilayer structure showed no macroscopic deformation in contrast to conventional methods and showed that additive manufacturing is possible.