| The effect of P addition on the formation of recrystallization texture in intersititial free (IF) extra low carbon steel sheet has been investigated. IF steel sheet exhibited high r-value texture (more specifically, {554}$lt;225$gt; type texture) independent of heating rate at the final annealing after cold rolling. Ti-P and Nb-P steels, however, enhanced near {100} grain provided that slow heating cycle, i.e., box annealing cycle was applied, and therefore r-value (deep drawability) is deteriorated for these steels. On the other hand, when rapid heating cycle, i.e., continous annealing cycle was applied for these steels, the growth of uncleated {100} grain was inhibited by large amount of recrystallized {111} grains, developing strong {111}({554}$lt;225$gt;) recrystallization texture. Futhermore, the {111} components increased with low finishing temperature at 800℃ in the hot rolling stage, was attributed to coarse precipitates of Fe(Nb, Ti)P in the matrix. It is considered that lowering the hot rolling temperature and adding the Ti and Nb can effectively reduce the grain boundary segregation of phosphorus, in the Fe-Ti(Nb)-P alloy, cause a decrease coarse precipitates on the grain boundary. |
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