porous ceramic filter China removes non-metallic inclusions in the aluminum alloy melt and adopts furnace flux treatment. The technology of ceramic foam filtration outside the furnace has long become an important means of purifying molten aluminum.
Reflected in the smelting process's alloying, purification, and refinement processing technology. The smelting of aluminum alloy is the first step in the aluminum alloy processing process, and it is also a crucial link.
Foam ceramic filter plate is a kind of porous ceramic product with opening porosity as high as 80-90%, volume density only 0.3-0.6gcm”, with a unique three-dimensional network framework and interpenetrating pore structure.
The earliest foamed ceramic filter plate was developed by FRMollard and Davison of Consolidated Aluminum in the United States in 1978 and used in the aluminum alloy pouring system. Their research results were published at the American Foundry Annual Conference in April 1980.
The foam ceramic filter plate filters and removes impurities, which can significantly improve the quality of ingots and reduce the waste rate. Since then, the corresponding research and development of foam ceramic filter materials have been promoted in the metallurgical industry.
The production of porous ceramic filter (CFF) generally uses a three-dimensional network structure and connected pores of organic foam as a carrier, immersed it in a special ceramic slurry with thixotropy and adopts a special roll extrusion process to make the ceramic The slurry is evenly spread on the skeleton of the carrier, but it is dried and solidified and then fired at a high temperature.
The foam ceramic filtration mechanism is generally described as diffusion interception and inertial collision interception or screening, sedimentation, and deep bed filtration.
The State Key Laboratory of Tsinghua University established a three-dimensional physical model and a two-phase flow model for the filtration mechanism of foam ceramics and carried out simulation calculations, which is very helpful for us to study the filtration and purification of molten aluminum.
However, the process of filtering and purifying molten aluminum by ceramic foam is very complicated, and it is also a complex process of high-temperature physical chemistry and metallurgical dynamics. As for screening collision, settlement, interception, and filtration, it is better to understand.
Correctly choose porous ceramic filter China to improve the cleanliness of aluminum melt
1. The selection of the porous ceramic filter plate is first determined according to the impurity content in the aluminum melt, the melt transfer flow rate, and the quality requirements of the final casting product.
①With a large amount of impurities, the quality of the casting products is average. A foam ceramic filter plate with a larger mesh can be selected, and a glass cloth coarse filter is added in front of the filter plate. At this time, it is important to use glass cloth to filter the semi-continuous casting first. It can intercept the slag when the eye is opened and the slag washed down by the launder to prevent the filter plate from clogging.
②The quality requirements of the casting products are high, and the new type of foam ceramic filter with small hole mesh, that is, a large mesh number, is selected.
Fujian Ruimin Aluminum and Southern Aluminum produce aluminum foil blanks, Henan Mingtai Aluminum produces high-quality hot-rolled slabs, Northeast Light Alloy Processing Plant produces high-quality military aluminum, and Guangdong Zhongshan Hesheng Aluminum produces high-quality industrial profiles All the products adopt the second-generation porous ceramic filter China made by AdTech.
The most prominent is the use of 30ppi and 60ppi specifications of 305x305x50. 381x381x50, 432x432x50, 508x508x50 two-stage filtration technology, to achieve the ideal cleanliness, and obtain good results.
③The selection of filter plate specifications is based on the flow rate and total throughput of the melt. If the flow rate is large, the total throughput is large, and the filter plate has small holes, a larger size is used.