TEXTURE DEVELOPMENT IN EXTRA LOW CARBON (ELC) AND INTERSTITIAL FREE (IF) STEELS DURING WARM ROLLING

摘要

The warm rolling and subsequent annealing textures of an extra low carbon (ELC) and two interstitial free (IF) steels have been investigated using both single pass and multipass rolling in the ferritic temperature range A total amount of 80 percent deformation by rolling was given in each case. It was observed that texture development in ELC and IF steels during warm rolling displays striking differences. In general, ELC steels acquire only a weak texture after finish rolling in the upper ferritic range, for both single and multipass rolling. Single pass warm rolling in the lower ferritic range, however, produces very sharp gamma fiber in this alloy, as an exception. Recrystallization anneal after warm rolling, in general, has been found to decrease the overall texture. By contrast, much sharper overall texture (and gamma fiber) develops in the IF steels during warm rolling, and it generally sharpens after subsequent recrystallization anneal. This is true for both single pass and multipass rolling. The best texture results (highest intensities of gamma fibers) are invariably obtained when most of the rolling deformation is given in the ferritic regime. Thus, between the two grades, the IF steels are definitely far better than the ELC steels for the purpose of developing sharp gamma fibers by warm rolling process. Out of the two IF steels, the Ti-containing steel appears to develop a perceptibly sharper gamma fiber after warm rolling and annealing as compared to the Nb-containing one.