Mechanical Properties of 3D Printed Carbon Fiber Composite

Carbon fiber reinforced polymer is mostly used to improve the performance of polymer-based component. Nevertheless, composite material properties depend on many factors such as fiber direction, length of fiber, matrix material and manufacturing process. This work aims to study the effect of fiber length and orientation on material stress-strain relationship. Short carbon fiber length (0.2 and 0.5 mm) reinforced with phenolic resin and long carbon fiber reinforced with commercial matrix material were studied. Long carbon fiber showed higher tensile strength than short carbon fiber with longitudinal direction, whereas slightly difference was observed for transverse direction. The printing path significantly affects failure location as area with lower fiber density exhibit lower local strength. Finite element simulation of the tensile test was carried out with the homogeneous material model which suggested that it could accurately predict the load capacity of printed composite. The bending strength was then computationally predicted. It was found that 0 degree offered higher bending load capacity than 90 degree orientation for all carbon fiber length with smaller difference with shorter fiber. Almost insignificant effect of fiber orientation was observed for 0.2 mm. fiber length.