Investigation on Tomographic-Based Nondestructive Characterization of Short Glass Fiber-Reinforced Composites as Obtained From Micro Injection Molding

Quantitative assessment of fiber characteristics in composite parts is of great significance in order to correlate them with the fiber-induced mechanical properties. X-ray computed tomography (CT) is being successfully used as a three-dimensional nondestructive measuring technique for the analysis of fiber characteristics (mainly the fiber orientation and fiber volume content) in fiber-reinforced composite materials. However, the accuracy of such analyses depends on various factors (e.g., scanning parameters, resolution), which is the motivation for this study. The current work investigates the effect of CT scanning parameters and spatial resolution on the obtained fiber orientation and fiber volume content. First a simulation study is carried out using a computationally generated fiber composite model followed by a validation using a thin-wall injection-molded part. The findings showed that the effect of CT settings is not significant on the measurements, but the resolution affects the estimated fiber volume content adversely. A preliminary error calculation method is proposed for correcting the overestimation in the fiber volume content.