The Recrystallization Behavior And Texture Evolution Of High-purity Aluminum Foils During Annealing

High-purity aluminum foils are the key raw materials for the anode of high voltage electrolytic capacitors, and the electric capacity is affected by the cube texture in aluminum foils. The stronger the cube texture is, the higher the content of capacity is. The evolution of cube texture in high-purity aluminum foils is influenced by many factors, such as hot rolling, intermediate annealing, cold rolling, the final annealing and the impurities, etc, which can make big differences on the final performance of the product. Among them are the cold rolling and the annealing who do the most. So, for many years, material scientific workers have focused on the evolution of macro textures under cold rolling and annealing processes, but most of them were based on symmetrical rolling, and did less in the continuous evolution of textures at the micro level.In the thesis, the high-purity aluminum foil was rolled at the speed ratio of1.06and1.13, respectively, and then annealed, in order to study how the annealing and early treatment work on the cube texture in high-purity aluminum foils. And then analyse the development of cube texture both in micro and macro perspectives were analysed to find the way to improve the proportion of cube texture, so as to provide a theoretical basis for processes.The results show that:intermediate annealing is a necessary process which can be beneficial to the development of the cube texture. With the rolling speed ratio of1.06, the transformation condition for the cube texture is more favorable. In a certain range, high annealing temperature can promote the development of cube texture. At500centidegree, and keeping the annealing time for5minutes, more cube texture proportion is obtained on the slower side. When introducing a first stage annealing at180centidegree for10minutes, the development of cubic orientation grains is more favorable than the others, also the average grain size can be controled under100nanometer.At the low annealing temperature like300centidegree, the evolution law of textures is the same, the cold rolling textures keep the opposite pace with the cube texture during annealing. And the transformation is mainly concentrated between10to20minutes. In the annealing process, firstly, the cubic nucleus are diffuse, and then expand into other grains with a high growth speed, finally they can swallow up most of the original grains, which makes the cube texture becoming the only main texture of the high-purity aluminum foil.