Preparation Of Mullite Fiber-Based Porous Ceramics By Light-curing 3D Printing
Jan 02, 2024Traditional molding technology can no longer meet the needs of various industries for high-precision, complex-structured mullite fiber-based porous ceramics. Light-curing 3D printing technology can directly produce ceramic materials of near-net size and is an ideal technology for preparing complex-structured ceramics. Using mullite fiber (matrix) and nano-SiO2 powder (high-temperature binder) as the main raw materials, mullite fiber-based porous ceramics were successfully prepared using light-curing 3D printing technology.
The effect of the added amount of nano-SiO2 powder (the added mass fraction is 0, 20%, 27%, 33% and 38% respectively) on the dispersion stability, rheological properties and photosensitive properties of the fiber slurry was studied, as well as its effect on the molar Effect of microstructure and physical properties of stone fiber-based porous ceramics. The results show that SiO2 powder significantly increases the viscosity of fiber slurry, which helps to alleviate the settlement and agglomeration of fibers and obtain a uniform printing slurry; however, excessive SiO2 powder will cause the slurry to be too viscous, which is not conducive to 3D printing. The process went smoothly.
When the SiO2 powder addition amount is 33% (w), the performance of the fiber slurry is most suitable for 3D printing. Its sedimentation rate within 1 h is less than 9.7% and the viscosity is 3.95 Pa·s (shear rate is 30 s-1 ); the mullite fiber-based porous ceramics printed with the above slurry showed the best physical properties (bulk density 0.56 g·cm-3, apparent porosity 72%, thermal conductivity 0.135 W·m-1·K- 1).