Abstract
The main purpose of this paper was to study systematically the development recrystallized textures of cold-rolled sheets of mild steel, such as aluminum killed steel and rimmed steel, by means of a three-dimensional orientation distribution function.
The deformation texture in cold rolling showed sufficient spreads, although {112} <110>, {100} <011> and {554} <225> orientations existed preferentially. The annealing of aluminum killed steel sheet below 600°C resulted in the gradual decrease of {100} <011> and {112} <110> components, but that annealing provided no drastic change in texture: the annealing texture were nearly the same as the deformed one.
The three-dimensional analysis showed that the texture of the sheet annealed above 600°C changed remarkably, i. e. {100} <0vw> components decreased repidly and {111} <uvw> group developed. Especially, the intensity of {111} <011> orientation grew stronger. It was observed during development of those recrystallized textures, that the dispersion of <110> fiber texture being parallel to the rolling direction decreased, and {112} <110> orientation disappeared gradually.
Another purpose of this paper was to carry out a precise analysis of fully recrystallized texture.
It has been said that the preferred orientation of recrystallized sheets of mild steel, especially that of aluminum killed steel sheet, is {111} <011> and {554} <225> according to the pole figure analysis; however, the three dimensional analysis has given no clear evidence that {554} <225> can be the highest intensity region. The discrepancy of the results given by these two analyses was explained by using the “three-dimensional orientation distribution function”, w(ψ, θ, φ).
From its definition, the pole density on “ND-RD axis”, the plane containing the ND axis and the RD axis, in {100} pole figure ought to agree with w(0, θ, φ). (ND is the normal direction, and w(0, θ, φ) is the average of w(ψ, θ, φ) with φ from 0 to π/2, when angle ψ is 0.) The results obtained showed that the values of w(0, θ, φ) agreed precisely with the pole density on the ND-RD axis of {100} pole figure. This fact leads to the clear conclusions that the highest intensity point of {554} <225> poles is due to w(0°, 60°, φ) and that the point is irrelevant to any preferred orientation.
