Ceramic foam filters making method
Polyurethane sponges were dipped into a slurry prepared with fused alumina powder and aluminum dihydrogen phosphate in order to obtain the green body. Ceramic foam filters were fabricated by pyrolysis of the green body at 800℃. The effect of aluminum dihydrogen phosphate content on micro-structure, volume density, linear shrinkage, and flexural strength of the ceramic foam filter was studied. The results show that when the aluminum dihydrogen phosphate content is less than 10%, the pore veins of alumina foam ceramics are broken and collapse and the mechanic's properties are poor. With the aluminum dihydrogen phosphate content increasing, the linear shrinkage of the alumina foam ceramics increases slightly, while the volume density and flexural strength rise sharply. When the aluminum dihydrogen phosphate content is 30%, the linear shrinkage of the alumina foam ceramics is 0.85%, the volume density is 1.21 g/cm3 and the flexural strength is 4.55 MPa.
The ceramic foam filter is one of the typical porous ceramic filter and honeycomb porous ceramics. Afterward, the third generation of the porous ceramic filter developed, in molten metal filtration, automobile exhaust purification, catalyst carrier, sound absorption, shock absorption, heat preservation, and production. It has a wide range of applications in implant materials, sensor materials, etc.
In recent years, the demand for high-performance foamed ceramics in the foundry industry has increased dramatically. There are many methods for preparing ceramics, such as the foaming method, and organic foam impregnation method. The sol-gel method, etc., in which the organic foam impregnation method has the advantages of less equipment and labor. The advantages of simple process and low manufacturing cost are widely used at present. Adtech uses fused alumina powder as raw material and aluminum dihydrogen phosphate as a bonding agent. Ceramic foam filters were prepared at low temperature, and aluminum dihydrogen phosphate has studied the effect of content on microscopic morphology, bulk density and linear shrinkage of alumina foamed ceramics rate and flexural strength.