| The technology of Compact Strip Production was a new producing hot rolling steel strips process received successfully in 1980s. Its merits are that invests in working cost is lower, the size of particle is finer, the intensity of products is higher, the dimension accuracy of board shape is higher, but at the same time shortcomings exist, for instance, the deep punching properties of cold rolling steel sheet based on CSP line is not better than that of cold rolling steel sheet based on conventional process route. Its are able to releat with the tissue and intensity of hot rolling steel strips based on CSP line and the regulation of evolution of texture and tissue of cold rolling steel sheet during the cold rolling and annealing process. So the paper will research on theories based on the problem.The hot rolling steel strips of 3mm after three kinds of heat treatments from CSP line was cold rolled to the reduction of 73.3% and 81.7% and 86.7%. The cold rolling samples were taken when the reductions are 32% and 61% during cold rolling process, and then the cold rolling finished products were annealed, the annealing process is the 10h of 680℃, the annealed samples were taken when 500℃﹑530℃,545℃,560℃,575℃,590℃,620℃,650℃,680℃,the 1h of 680℃,the 3h of 680℃and general temperature. EBSD researches on Evolution of tissue and texture during the cold rolling and annealling process, the mechanism of formed nucleus, the temperature scope of recrystallization and the misorientation angle of nucleus. So the studied results provide academic basis of cold rolling steel sheet,when working out cold rolling and annealing process.The results show:1)The hot rolling steel strips of 3mm after heat treatment process No.1 was cold rolled to 0.55mm by the reduction of 81.7%, whice have lower initiatory recrystallization temperature and earlier recrystallization over and thiner annealed particles and homogeneous annealed tissue than the cold rolling samples after other process basied on the paper.2)The raw material texture of cold rolling steel sheet affect greatly evolution of texture during the cold rolling process, for the cold rolling sample of 0.55mm, slippage system of {110} moves at the beginning during the cold rolling process, leading to forming the {112}<110> texture of 31.1% and {001}<110> texture of 14.7% of cold rolling finished product, while {111} texture of 39.2% was formed by shear stress. 3)For the cold rolling sample of 0.55mm, Recrystallization is from 530℃to 590℃, and the complete recrystallization temperature is 590℃, The new nuclei have a high misorientation angle of 25o~55o with the surrounding deformed matrices when recrystallizing. {111} texture take place great changes during the early stage of recrystallization, whereas {001}<110> and{112}<110> textures take place great changes during the late stage of recrystallization, stored energy of {111} texture is the highest and stored energy of {112}<110> texture is higher than that of {001}<110> texture, the mechanism of early formed nucleus(before 545℃)belong to the mechanism of orientational formed nucleus.4)For the cold rolling sample of 0.55mm from Baogang CSP plant, the value of r is 1.7075,and the value of ?r is 0.0833 by the double steps annealing(the annealing process is the 2h of 575℃and the 8h of 680℃).
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