Delamination analysis of 3D-printed nylon reinforced with continuous carbon fibers

The inconsistent interfacial bonding of 3D-printed materials is accompanied by increasing scattering of the measured fracture toughness in delamination tests. This article focuses on the analysis of the delamination tests using theories developed for conventional composites. To this end, nylon 3D-printed specimens reinforced with carbon fibers are subjected to the mode I Double Cantilever Beam (DCB) and the mode II End-Loaded Split (ELS) tests. Several analytical methods and numerical models are employed to measure the fracture toughness and simulate the behavior of the specimen during delamination. The uncertainty of the data is considered by expanding the deterministic character of the models utilizing the non-intrusive stochastic pseudo-spectral projection method. The results of the simulations are well in agreement with the experimental results and support the use of stochastic techniques in combination with linear fracture mechanics for the delamination analysis of 3D-printed composites.