A comparative study of precipitation effects in Ti only and Ti–V Ultra Low Carbon (ULC) strip steels

Two ULC steel grades were investigated, one based on combined vanadium and titanium additions and the other based on titanium only additions. It has been established that TiC formation during interphase precipitation retards grain growth of the {111} texture grains during continuous annealing and hence positively affects the r value of the Ti only steel. The formation of newly formed TiC precipitates on dislocations during continuous annealing has been found to result in an increase of the yield strength in both steel grades, as the annealing temperature is increased. It is also confirmed that VC particles formed during the coiling process dissolve during the continuous annealing cycles. Suitable continuous annealing cycles can be adopted to produce high formable steels with a bake hardening potential using the beneficial effects of combined Ti–V additions.