Effect of Al and Mo on the textures and microstructures of dual phase steels

The effect of Al and Mo addition on the development of microstructures and textures of dual phase steels for the usage in car outer panel was studied. The two elements were separately added to a base alloy to compare their effects on the microstructures and textures along the processing route from hot rolling to annealing. They showed common consequence of grain refinement of hot bands, which resulted in the suppression of deformation heterogeneities during cold rolling, subsequently enhanced the desirable γ-fiber and removed some detrimental minor components in the annealing textures. The effect of Mo was stronger than Al, which could be attributed to the fixation of solute C by Mo.

► Addition of Al and Mo improved the annealing textures of dual phase steels.
► Some detrimental components of annealing textures are introduced by shear bands.
► Grain refinement of hot band via alloying suppresses the development of deformation heterogeneities during cold rolling.
► Mo has positive effects both on the annealing texture and the attainment of dual phase structure.