Study On Microstructure Control And Mechanical Properties Of Cast Rolled Aluminum Alloy Sheet

3003 aluminum alloy is al Mn alloy,which has a series of excellent properties,and is widely used in the fields of fin aluminum foil,packaging container,etc.Compared with the traditional ingot hot rolling method,the continuous casting rolling method has the advantages of simple equipment,low cost and short production cycle,which greatly simplifies the production process of aluminum alloy plate,strip and foil and improves the economic benefits.However,in the continuous casting and rolling process of Al Mn series alloy,the solidification speed of aluminum liquid is very fast,a large number of Mn elements are dissolved in the aluminum matrix in the form of supersaturation,which leads to the formation of abnormally coarse and uneven recrystallization structure in the annealing process of cold rolled sheet,resulting in the poor plasticity of continuous casting and rolling 3 series aluminum alloy sheet,which is difficult to be used in the production of deep drawing aluminum products with high elongation requirements,which is seriously limited its application range is also given.In this paper,the effects of homogenization annealing process and finished product annealing process on the structure and properties of CC 3003 aluminum alloy sheet are studied.On this basis,the continuous casting rolling process is adjusted,and the problems of poor plasticity and deep drawing performance of Cast-rolled 3003 aluminum alloy sheet are attempted to be solved by combining homogenization,rolling and finished product annealing process optimization.The results show that the edge of the plate is elongated grain structure,while the center of the plate is uniform fine grain.When the homogenization temperature is low,the microstructure of cast rolling plate is basically unchanged.When the homogenization temperature rises above 595 ?,the grains of both sides and cores grow up significantly.After high-low temperature two-stage homogenization and low-high temperature two-stage homogenization,both the edge and the center of the cast rolling plate are coarse grains of millimeter grade.The precipitation of the second phase increases with the increase of homogenization temperature.After homogenization treatment at 550 ?,the content of Mn solid solution is the lowest.When the homogenization temperature is further increased,part of the precipitated phase will be dissolved back,which leads to the recovery of the solid solution of Mn in the cast rolling plate.After cold rolling and annealing,it is easy to form the distribution characteristics of large and long edge grains and small and equiaxed core grains,and the overall grain uniformity is poor.By shortening the length of casting rolling zone in continuous casting rolling process,the homogeneity of microstructure and the distribution of solid solution of Mn element in casting rolling plate can be significantly improved.Furthermore,the non-uniformity of the recrystallization structure is improved,and the change of the recrystallization structure is smaller with the increase of the annealing temperature.Through the above process optimization,the CC 3003 aluminum alloy plate with excellent properties was finally made,its tensile strength is more than110 MPa,and its elongation is 40%.