초록(영문)
3D printing technology has rapidly grown and is currently used in various fields, leading to high importance in structural health monitoring of 3D printed materials. We have focused on a nondestructive evaluation method involving ultrasonics and analyzed anisotropy through propagation characteristics. We mainly analyzed anisotropy depending on the printing direction. In this experiment, we used a cube-type specimen and a plate-type specimen, and we analyzed two types of filament direction: [0] and [0, 90]. For the cube-type specimen, a pulse-echo-based method was used, and for the plate-type specimen, a pitch-catch-based method was used. Results showed that for the cube-type specimen, a z-direction anisotropy was observed, and for the plate-type specimen, the [0] specimen showed greater speed in the filament direction, and the [0, 90] specimen was symmetric with respect to the 45-degree line. We could also observe some unwanted signals reflected by the space between layers.