| 초록 |
Powder based three dimensional printing (P-3DP) enables shaping of complex glass structures. Powder characteristics are important factors affecting physical properties of final products such as bulk density and strength. Sintering process of three dimensional green bodies made with amorphous oxide glasses should be optimized due to the viscous flow of the glass with increasing temperature. In this study, we investigated the effect of powder characteristics such as shape and particle size distribution on printed structures, and optimized sintering condition for the 3D glass structures. The SiO2-ZnO-B2O3 glass system was used as a printed material with different particles size (13μm, 22μm, and 39μm) and shape (irregular and spherical). The densification behavior of the glass was analyzed by a hot stage microscopy to optimize the sintering profile. The irregular shape of fine powders (13μm and 22μm) showed strong agglomeration during printing process, whereas spherical fine powder (D50=11μm) and 39μm powder showed excellent printing accuracy without any defects. Densification rate of green bodies at a fixed viscosity points is dependent on the sintering time, and it reduced the anisotropic shrinkage behavior. The complex geometries of the 3D-printed structures were stabilized at between first shrinkage temperature and maximum shrinkage temperature. |
