AdTech offers an alumina ceramic foam filter for filtering molten metal, a honeycomb ceramic, or a honeycomb structure, the cells extending from one side to the other, usually used to filter molten metal before or during casting.
Due to the dimensional change of the ceramic foam filter in a particular nominal size, and in the case of filtering molten metal in a permanent mold or mold erosion on the mold surface or in the coating can be applied to the thickness variation of the mold surface, there is a metal by passing the outer surface of the filter around it allows some unfiltered metal to pass through the instrument or into the mold. In extreme cases, the filter may actually move out of the proper position during the casting process. Therefore, the filtration efficiency of the cast metal is lowered to form a non-metallic inclusion.
It is well known that the surface of an aluminum liquid filter is used in conjunction with ceramic fibers in filtering device to secure and seal the filter in place. Since the gasket is soft, it will not wear out, it will be damaged during transportation or handling, the fiber will fall off the gasket and pass through the filter device or into the mold or mold. It has now been found that by surrounding the fiber liner with metal foil.
The outer surface of the aluminum liquid filter is surrounded by a gasket made of a fibrous material, characterized in that the metal foil is fixed to a gasket around the outer peripheral surface of the gasket, and the cross-section of the alumina ceramic foam filter may be any shape, but usually round, square or rectangular, the gasket can be made of a soft, flexible ceramic fiber material. This material is preferably free of organic compounds to avoid the possibility of hydrogen gas when metal is filtered from metals such as aluminum.
The thickness of the strip is usually from 3 mm to 6 mm, such a strip can be compressed to 1 to 2 mm. Alternatively, the gasket can be made of woven fiberglass cloth. The width of the gasket may be the same as or less than the thickness of the filter. The metal foil should be made of the same or compatible metal as the cast metal. The metal foil can be fixed to the gasket by an adhesive, preferably self-adhesive aluminum foil. The amount of adhesive used should be as small as possible to minimize the possibility of metal contamination. The width of the metal foil can be the same or slightly larger than the width of the filtering molten metal gasket. In this way, the gasket including its edges is completely surrounded by a foil, and the thickness of the foil is preferably 0.01 to 0.10 mm.
