Process-structure-property analysis of short carbon fiber reinforced polymer composite via fused filament fabrication

This study investigates the effects of process conditions on the inherent variabilities in fused filament fabrication (FFF) of short carbon-fiber-reinforced Nylon-6 composites, where the sources of uncertainty and their adverse effects on microstructures and Young's modulus are quantified. Microstructural characteristics such as fiber volume fraction, void volume fraction, and their spatial distributions are first extracted via image-based data analytics, and then their uncertainties are quantified by the analysis of variance. A Monte Carlo sampling method is introduced to enrich the datasets for analyzing uncertainty propagation from micro-level (microstructures) to macro-level (mechanical property). A modified Halpin-Tsai model with the consideration of fiber and void distributions is developed to quantify the propagated uncertainties on Young's modulus, which are further validated through quasi-static tensile tests. This study examined the process-structure-property relationship of FFF samples and quantified the underlying variations in both micro- and macro-levels.