These ceramic foam filters for foundries are designed for molten metal casting. Ceramic foam filters have good thermal properties and mechanical properties for high-temperature environments.
Currently, in the molten and casting process of various metals, the rate of casting waste is usually reached 60 ~ 80% due to non-metallic impurities and pores defects. Casting defects not only have a strong impact on casting performance and mechanical properties, but also have a detrimental impact on the appearance of process and casters. By filtration of molten metal, it can effectively reduce various non-metal inclusions to obtain high-quality castings.
The molten metal was currently filtered and purified by ceramic foam filters for foundries. The use of ceramic foam filters has low cost, more energy-saving, high-temperature impact, and thermal stability, which can avoid the pollution of molten metal.
Thanks to the mechanism of creation of the “filter cake” on the inlet filter side and thanks to depth filtration inside the ceramic matrix, these ceramic foam filters are an effective instrument to reach metallurgical purity of molten metal during the process of casting. The filters also calm mold filling, thus preventing the creation of undesirable defects in the casting.
These ceramic foam filter features are conditioned by the open 3D structure of the ceramic matrix created by the system of mutually interconnected cells. They are characterized by very good thermal conductivity, stability, and resistance to sudden temperature changes.
Ceramic foam is a tough foam made of ceramic. The manufacturing technique involves impregnating open-cell polymer foam with ceramic slurry inside and then firing it in a kiln, leaving only the ceramic material. Ceramic foam can be composed of several ceramic materials. Common high-temperature ceramics are alumina, silicon carbide, zirconia, and etc. Unlike asbestos and other ceramic fibers, ceramic foam is completely harmless and is the best in insulation materials. Its high strength and hardness also make it useful as a structural material for low-stress applications.