Nonlinear vibratory properties of additive manufactured continuous carbon fiber reinforced polymer composites

Often, the responses of additive manufactured parts are studied only in the context of static loads, since most consumer-grade additive manufactured parts are not capable of supporting dynamic loads. Here, the effects of fabrication parameters on the vibratory properties of 3D-printed polymer composite beams were studied. A total of 420 vibratory system identification experiments were conducted on 70 additive manufactured cantilever beams. In addition, Euler-Bernoulli beam theory and the finite element method were used to estimate the first natural frequency of the beams. It was found that build parameters change not only the stiffness of the beam, but these build parameters also affect the damping ratio. Furthermore, the frequency response of the beams is amplitude-dependent; this nonlinear effect is important in predicting the behavior of 3D printed structures. The complex relationship between the build parameters and the nonlinear vibratory response points to the possibility of creating tailored vibratory responses of 3D-printed structures. Since vibrations can cause accelerated wear, this work could also be important in determining accurate life cycle predictions of additive manufactured parts.