Removal of inclusions from industrial pure molten aluminum(A01) by stirring active molten flux was studied. Wettability of nonmetallic inclusions in the molten aluminum was worse than that in active molten flux. Accor...Removal of inclusions from industrial pure molten aluminum(A01) by stirring active molten flux was studied. Wettability of nonmetallic inclusions in the molten aluminum was worse than that in active molten flux. According to the surface renewal model, the inclusions were easily transferred into molten active flux from fine aluminum droplets and then reacted chemically when molten aluminum was dispersed into fine aluminum droplets in stirring active molten flux. Tensile tests show that tensile strength of purified tensile sample(as-cast) increases by 8.59%. SEM photographs show that the fracture cracks of purified tensile sample are homogeneous, and the dimples are small and homogeneous. From metallographs and statistic results of Leco analysis software, it is found that the quantities and sizes of the inclusions in purified sample are obviously fewer and smaller than in unpurified tensile sample(as-cast).展开更多
Various purification methods were explored to eliminate the dissolved hydrogen and nonmetallic inclusions from molten aluminum alloys. A novel rotating impeller head with self-oscillation nozzles or an electromagnetic...Various purification methods were explored to eliminate the dissolved hydrogen and nonmetallic inclusions from molten aluminum alloys. A novel rotating impeller head with self-oscillation nozzles or an electromagnetic valve in the gas circuit was used to produce pulse gas currents for the rotary impeller degassing method. Water simulation results show that the size of gas bubbles can be decreased by 10%20% as compared with the constant gas current mode. By coating ceramic filters or particles with active flux or enamels, composite filters were used to filter the scrap A356 alloy and pure aluminum. Experimental results demonstrate that better filtration efficiency and operation performance can be obtained. Based on numerical calculations, the separation efficiency of inclusions by high frequency magnetic field can be significantly improved by using a hollow cylinder-like separator or utilizing the effects of secondary flow of the melt in a square separator. A multi-stage and multi-media purification platform based on these methods was designed and applied in on-line processing of molten aluminum alloys. Mechanical properties of the processed scrap A356 alloy are greatly improved by the composite purification.展开更多
文摘Removal of inclusions from industrial pure molten aluminum(A01) by stirring active molten flux was studied. Wettability of nonmetallic inclusions in the molten aluminum was worse than that in active molten flux. According to the surface renewal model, the inclusions were easily transferred into molten active flux from fine aluminum droplets and then reacted chemically when molten aluminum was dispersed into fine aluminum droplets in stirring active molten flux. Tensile tests show that tensile strength of purified tensile sample(as-cast) increases by 8.59%. SEM photographs show that the fracture cracks of purified tensile sample are homogeneous, and the dimples are small and homogeneous. From metallographs and statistic results of Leco analysis software, it is found that the quantities and sizes of the inclusions in purified sample are obviously fewer and smaller than in unpurified tensile sample(as-cast).
文摘Various purification methods were explored to eliminate the dissolved hydrogen and nonmetallic inclusions from molten aluminum alloys. A novel rotating impeller head with self-oscillation nozzles or an electromagnetic valve in the gas circuit was used to produce pulse gas currents for the rotary impeller degassing method. Water simulation results show that the size of gas bubbles can be decreased by 10%20% as compared with the constant gas current mode. By coating ceramic filters or particles with active flux or enamels, composite filters were used to filter the scrap A356 alloy and pure aluminum. Experimental results demonstrate that better filtration efficiency and operation performance can be obtained. Based on numerical calculations, the separation efficiency of inclusions by high frequency magnetic field can be significantly improved by using a hollow cylinder-like separator or utilizing the effects of secondary flow of the melt in a square separator. A multi-stage and multi-media purification platform based on these methods was designed and applied in on-line processing of molten aluminum alloys. Mechanical properties of the processed scrap A356 alloy are greatly improved by the composite purification.
