Preparation and Performance of Aluminosilicate Fibrous Porous Ceramics Via Vacuum Suction Filtration

This study successfully prepared high-porosity aluminosilicate fibrous porous ceramics through vacuum suction filtration using aluminosilicate fiber as the primary raw material and glass powder as binder, with the appropriate incorporation of glass fiber. The effects of the composition of raw materials and sintering process on the structure and properties of the material were studied. The results show that when the content of glass powder reached 20 wt% and the samples were sintered at the temperature of 1,000 ℃, strong bonds were formed between the binder phase and fibers, resulting in a compressive strength of 0.63 MPa. When the sintering temperatures were increased from 1,000 ℃ to 1,200, the open porosity of the samples decreased from 89.08 % to 82.38 %, while the linear shrinkage increased from 1.13 % to 10.17 %. Meanwhile, during the sintering process, a large amount of cristobalite and mullite were precipitated from the aluminosilicate fibers, which reduced the performance of the aluminosilicate fibers and hindered the comprehensive improvement in sample performance. Based on these conditions, after adding 30 wt% glass fiber and being sintered at 1,000 ℃, the sample exhibited higher compressive strength (1.34 MPa), higher open porosity (89.13 %), and lower linear shrinkage (5.26 %). The aluminosilicate fibrous porous ceramic samples exhibited excellent permeability performance due to their high porosity and interconnected three-dimensional pore structures. When the samples were filtered at a flow rate of 150 mL/min, the measured pressure drop and permeability were 0.56 KPa and 0.77 × 10^-6 m² respectively.