Acoustic Measurements on Synthetic Fractured Samples Made Using FDM 3D Printing Technology

Abstract

This paper presents the acoustic measurements results on synthetic samples containing a system of oriented disc-shaped cracks simulating a fractured medium. An effective model for such media is a model with a transversely isotropic symmetry system under the condition that the host medium is isotropic. FDM 3D printing technology with molten plastic thread was used to form synthetic samples. The results of the recorded acoustic measurements have shown the occurrence of anisotropy of the host medium due to horizontal layering of plastic threads. In the case of printing internal cracks using this technology, the samples contain inhomogeneities due to the greater sintering of plastic threads around the cracks. It was also shown that the use of SLA technology (printing from liquid photopolymer) potentially avoids the indicated effects, but requires developing the technique for printing samples with cracks. Acoustic measurements on the sample without cracks formed by this technique confirmed its isotropy.