Study On The Preparation, Micro Structure And Properties Of Largescale3104Alloy For Canbody Application

Supported by the aluminum corporation of China technical fund,3104aluminum alloy strips used for canbody were investigated by the methods of micro-hardnessTesting, property testing, optical observation, SEM, TEM, XRD and JMatPro software simulation. The whole key processes for homogenization, hot rolling and cold rolling were studied. Based on this, the relationship between microstructures and properties was further discussed. The main results of the research are as follows:(1) Macro-segregation exists in the cross-sections of3104aluminum alloy largescale ingot, From the surface to the center of the ingot, The maximum differences of Ti contents reached0.025%, and the maximum differences of Mg contents reached0.34%, the rule of segregation is reverse,the grain and initial compounds size increase from surface to center of ingot. The micro-segregation was inhomogeneous at different positions, Mg distributed homogeneously in the surface of ingot and in-homogeneously in the center of ingot. It is necessary to homogenize for the largescale ingots.(2) With the increase of homogenization temperatures and the prolongation of homogenization time, the micro-segregation in the grains gradually decreased, the difference of micro-hardness gradually decreased.(AlMnSi) and (AlMnFeSi) phase precipitated in the grains. Homogenized below590℃, precipitates is small, and the distribution is uneven, in the grain and on the boundary is few. Homogenized up600"C, the intensity of precipitates decreased and the size of precipitates increased, the distribution is more homogenous. Meantime, the aluminide gradually dissolved and parts of Al6(FeMn) phase gradually transformed into a-Al12(MnFe)3Si phase. Under the production conditions, the proper homogenization treatment for3104ingot is600℃/8-12h.(3) The surface, center and interlayer of hot roughing sheet consisted of fully recrystallized, hot-rolling deformed and uncompletely recrystallized structure. The initial compounds were broken and distributed in-homogeneously. After hot finish rolling, the whole section of strip consisted of fully recrystallized structure.(4) The final rolling temperature and cooling rate had great and obvious effect on the structure of hot finishing trips. The final rolling temperature were higher and the cooling rate were lower, the content of cube texture was higher. When the final rolling temperature was340℃and the cooling rate was1℃/min, the content of cube texture increased from30%in hot roughing sheet into above60%in hot rolled trip.(5) During cold rolling, with the increase of cold rolling reduction, the size of the second phase decreased in the center of the material. After cold rolling, the structure inhomogeneity of the ingot can not be eliminated ultimately. The cold reduction and cooling rate affect the kinds of texture, but the final rolling temperature has no obvious effect.(6) The contents of clod rolling texture and earing were affected by deformation rate, final rolling temperature and cooling rate. With the increase of cold rolling reduction and the decrease of final rolling temperature, the intensity of α、β deformation texture is higher, the deformation texture and earing ratio increased. At the same final rolling temperature, the intensity of β texture and earing ratio were higher under the slow cooling rate. Due to the inhomogeneity of cooling rate, the earing ratio were higher at the edge of strip than at the center of strip.(7) The3104canbody with low Fe/Si ratio and Fe content have higher Cube texture, lower earing ratio, higher content of Al(Fe,Mn,Si) phase, smaller compound particles, appropriate mechanical properties and better performance properties.