The importance and meaning of melt-treatment of molten Al

and the theory of high-efficient melt-treatment of Aland its key technique were analyzed in this paper

and the effect of melt-treatment techniques such as high-efficient purification

modification of Fe-rich impurity-phase and grain refinement

and interrelations among these treating techniques of molten Al were investigated.It is firstly put forward that the purification is the fundamental and the key processes

i.e.

the basic of modification and grain refinement processes.Based upon this viewpoint

a new synthetical technique of high-efficient melt-treatment of Al has been developed

and it has been applied into the preparation of Al sheetsused for canwith high-performance.The new technique makes the metallurgical quality of Al sheetshave been improved remarkably.For this reason

the mechanical properties（especially plasticity） of Al sheetshave been improved remarkably.The new techniquealso will have the value of direct application in other Al sheets with high-performance.