Deep Filtration of Molten Aluminum using Ceramic Foam Filters and Ceramic Particles with Active Coatings

摘要

The inclusions in molten aluminum were removed using the deep filtration of ceramic foam filters and ceramic particles with active coatings. The results of tensile tests showed that the elongation of the filtered tensile specimen S6 increases by 17.93 pct, but the tensile strength does not. The scanning electron microscope (SEM) examination showed that the secondary cracks and dimples in the filtered tensile specimen S_6 were finer and more homogeneous than those in the unfiltered tensile specimen S_0. In addition, metallographic examination showed that there were only a few inclusions of approximately 6 (mu)m in diameter in the filtered specimen S_6, but more inclusions of approximately 40 (mu)m in diameter were found in the unfiltered specimen S_0. The filtration efficiency of the coated ceramic particles was higher than that of the coated ceramic foam filters. The active coating could effectively capture the inclusions and dissolve Al_2O_3 in them during filtration.