Investigation On Texture Controlling Of High Purity Aluminum Foils By Cross Shear Rolling

High purity aluminum foils are the key raw materials of high voltage electrolytic capacitors. Since the aluminum foils for high voltage anode materials were subjected to DC electrochemical etching, tunnel growth of etch pits with the <100>crystallographic grain during corrosion were achieved, which were required for high capacitance, thus the large volume fraction of cube texture in the aluminum foils is the prerequisite to obtain high capacitance. To obtain the stronger cube texture {001}<100>, the researches on texture formation in the high purity aluminum foils have been done for a long time and a lot of great progress in this field has been made especially in recent years. However all of the achievements are obtained under the condition of symmetrical rolling. In this thesis, the behavior of micro-orientation flow of high purity aluminum foils by cross shear rolling was studied in order to obtain the strongest cube texture.In this thesis, the high purity aluminum sheet provided by Southwestern Aluminum Manufacture Factory was cold rolled and subsequent annealed by different technological methods. The X-ray texture analysis were performed for various specimens, the microstructures of some specimens were observed with transmission electron microscope, microtextures analysis was performed by EBSD, combining the results of different parts, the effects of several technological parameters on the textures and microstructures of the high purity aluminum foils by cross shear rolling were then discussed to some extent. The nucleation and growth behaviors of cube orientation grains during the early stage of recrystallization annealing after cold rolling were discussed, so that the formation and development of cube texture in high purity aluminum foils can be controlled more systematically.The research results show that there is a great difference in cold rolling texture between cross shear rolling and the symmetric rolling. Under the condition of cross shear rolling, the textures formed near slow roller side and fast roller side were obviously different, especially in the content of the rotation-cube texture {001}<110>. With the increase of reduction near fast roller side, the cold rolling textures were mainly S {123}<634>and {102}. However, the cold rolling textures near slow roller side were mainly C {112}<111> and {001}<110> rotation-cube texture. In addition, the deformed texture distribution in high...