| Aimed at the currently existing problems, that is metallurgical quality of aluminum sheet made in china is lower than that of other country, which has a direct effect on the forming properties of this material, the widely used high perforations aluminum sheets (e.g. aluminum sheet used for the easy-open can) are selected as the main research object. Based on the previous successful research work about aluminum sheet used for pressure can , the technologies of the melt-treatment including the high-efficient purification, grain refinement, and modification, and their effect on improving the metallurgical quality of aluminum sheet were systematically studied. At the same time, relationship among the purification, refinement and modification of molten aluminum is also studied with aids of the advanced analyses and testing techniques, such as OM, SEM, ED AX, DTA, XRD, and mechanical properties. Thus expounding further the important role of the high-efficient purification in the melt-treatment of aluminum. In the end, the effect of technique of synthetically melt-treatment was testified in the practical production. The main results as follows:1) The ingredients of the flux for removing inclusions have the decisive influence on the effect of purification. Its components affect the physical and chemical properties of the flux (e.g. melting point, angle of the moisture, surface tension .etc) directly, thus in the thermodynamics and kinetics of the purification for removing inclusions, Therefore, The design of the flux must be base on the thermodynamics and kinetics of the purification.2) The high efficient flux purification for removing inclusion which is suitable for aluminum sheet used for the easy-open can or for the electrical aluminum rod is YJ-1 and DJ-1 respectively. Using these fluxes and the appropriate treating technique, both the contents of the inclusions and porosity of aluminum sheet can be reduce remarkable, the role of removing inclusions could amount to 91.3% and 83.6%, and the content of porosity could amount to 94.2% and 91.2% respectively, thus making the mainly harmful effects of metallurgical defects on the properties of aluminum be diminished.3) The master alloy suitable aluminum sheet used for easy-open can is Al-5Ti-B imported. The mast alloy Al-5Ti-B made in china is suitable for refinement of the electric aluminum rod.4) After aluminum sheet used for easy-open can was treatment with the modification addition agent M3, the coarse or skeletal Fe-rich impurity phases in this material could be transformed into tiny, sphere /short stick form, and distributed uniformly, thus increasing the mechanical properties of aluminum sheet, especially theincreasing rate of elongation amount to about 67.7%.5) Metallurgical quality of aluminum sheet used for easy-open can can be improved after the synthetically melt-treatment, thus improving the properties of aluminum sheet, especially the extending rate of elongation can be increased by 112.8%. When this technology are used for practical production, the mechanical properties of the aluminum sheet as-cast ,as-homogenization , as-rolled, as-annealed, can be increased remarkably , comparing with routine melt-treatment, At the same time ,the high-efficient purifying fluxes for removing inclusions, DJ-1 flux have a great effect of purification on the electrical aluminum rod.6) The technology of purifications based on the removing inclusions has the excellent purifying effect on molten aluminum, removing inclusions is the foundation of eliminating the porosity. After the high-efficient purification, the effect of the modification and refinement of master alloy could be put into full play respectively. Therefore the purification is the key technique of the melt-treatment of aluminum. The purification is the foundation of grain refinement and modification. It is further showed that the principle of the melt-treatment of aluminum, put forward in the previous research of the aluminum sheet used for the pressure can, also has the common guiding e...
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