Effect of hot-band annealing condition on secondary recrystallization in grain-oriented 2.3%Si-1.7%Mn steel

The effect of hot-band annealing temperature on secondary recrystallization was investigated using the hot-rolled steel sheets containing ultra-low C- 2.3%Si-1.7%Mn-0.01%sol.Al of 2.3 mm thickness. The followings were found. When the hot-bands doesn't recrystallize after the hot-band annealing at 60 0 and 625 degrees C, secondary recrystallization of the {110}< 001 > orient ation mixed with the {211}< 011 > orientation forms. This is because the {1 10}< 001 > orientation density is too weak in the primary recrystallization texture, That also occurs when the inhibitor is too weak in the secondary recrystallization stage, Fully recrystallized hot-band after annealing at 7 00 degrees C leads to no secondary recrystallization. The reason is that ve ry coarse primary recrystallized grains at the center layer prevent seconda ry recrystallization. Secondary recrystallization of the {110}< 001 > orien tation evolves completely when only near surface layer but not the center l ayer of the hot-band recrystallize after the hot-band annealing at 650 and 675 degrees C. The reason is because amount of {110}< 001 > component in th e primary texture, the inhibitor intensity and the primary matrix grain siz e structure are satisfied.