In recent years, 3D printers have increasingly been used to manufacture final products in the medical field and other applications. However, there is currently no established method for evaluating the lifespan of materials used in final products under high-load conditions. In this study, we applied the acoustic emission (AE) method to observe the failure behavior of 3D-printed materials during fatigue testing. In that testing, rubbing occurs between fracture surfaces—a phenomenon that does not appear in tensile tests. This rubbing significantly affects the characteristics of the AE signals detected during testing. As a result, there were notable differences in the outcomes of chaos analysis between fatigue and tensile tests. These differences suggest that the presence of rubbing alters the nonlinear dynamics of the signals. Therefore, we investigated whether it is possible to extract the rubbing component from the signals obtained in the testing and conduct an evaluation that is comparable to that of tensile tests. By separating this component, we aim to clarify the intrinsic failure behavior of the material and enable more accurate assessment of its durability under cyclic loading.
Niki et al. (Wed,) studied this question.