Evolution of textures in interstitial free steel during multiple cold rolling and annealing

Abstract

A Ti bearing interstitial free (IF) steel was finish rolled in the ferrite zone and the texture evolution during double cold rolling (DCR) and double annealing technology was investigated by orientation distribution function (ODF). The γ-fibre texture of DCR has been compared with traditional single cold rolling (SCR) and annealing. The SCR annealing texture component {1 1 1} 〈1 1 2〉 remained after DCR and it improves the formation of {1 1 1} 〈1 1 0〉 during DCR annealing. During rolling process the gliding planes will usually rotate towards rolling plane. The rotation could not be achieved totally due to the deforming resistance from crystal defects. The result is that {1 1 1} turn to parallel the sheet plane and form. The in-grain shear bands observed after DCR play a major role on the rotation and improve the γ-fibre texture indirectly. The mean plastic strain ratio ( r-value) of DCR is much higher than that of SCR. The work hardening coefficient ( n-value) less relies on the rolling and annealing technology.