No abstract

The cold-rolling texture of fcc sheet metals with medium to high stacking fault energies is known to consist of the brass {011}<211>, Cu {112}<111>, Goss {011}<100>, S {123}<634>, and cube {100}<001> components. The recrystallization (Rex) texture of cold-rolled Al, Cu and their alloy sheets is well known to be the cube texture. The 40°<111> orientation relationship between the S and cube components, which has been taken as a proof of the oriented growth theory, has made one believe that the S orientation is responsible for the cube Rex texture. The oriented growth theory is claimed to be associated with grain boundary mobility anisotropy. However, some data indicate the Cu component is linked with the cube component. There is no 40°<111> orientation relationship between the Cu and cube components. The strain-energy-release-maximization model (SERM), in which the strain energy due to dislocations is importantly taken into account, suggests that the Cu and S components in the rolling texture are linked with the cube and ~{031}<100> components in the Rex texture, respectively.

In 1995, the author advanced a model for the evolution of recrystallization texture. In the model the absolute maximum internal stress direction due to dislocations generated during deformation or fabrication in the fabricated material is aligned with the minimum Young's modulus direction in recrystallized gains, whereby the energy release during recrystallization can be maximized. This comes from the fact that material concerned does not change macroscopically its shape and volume during recrystallization, and so the recrystallization is a displacement controlled process. This strain energy release maximization model originates from the presumption that the stored energy due to dislocations is the major driving force for the recrystallization. The absolute maximum internal stress direction may be obtained from the operating slip systems, which are related to the deformation mode and texture. If one slip system is activated, the absolute maximum normal stress direction is parallel to the slip direction, or the Burgers vector direction. If more than one slip system is activated, the absolute maximum normal stress direction can be determined by the vector sum of related slip directions, taking their contribution to slip into account. This paper discusses recrystallization textures of plastically deformed and electrodeposited metals, based on the model. A brief comment was made also on the growth textures of axisymmetrically deformed copper and silver and electrodeposited silver and Fe-Ni alloy.

No abstract

The {110}<112> rolling texture of Cu-22%Zn and Cu-30%Zn sheets having relatively low stacking fault energy transforms into the {236}<385> texture after recrystallization. The 40°<111> relation is approximately satisfied between the {110}<112> and {236}<385> textures. The 40°<111> relation is often addressed as a token of the oriented growth theory for the recrystallization texture evolution. On the other hand, Cu-16%Mn and Cu-1%P alloys and high Mn austenitic steels such as Fe-18%Mn-0.6%C, Fe-18%Mn-1.5%Al-0.6%C, and Fe-18%Mn-3%Al-0.6%C sheets having relatively high stacking fault energy also have the {110}<112> rolling texture, which transforms into the {110}<001> texture after recrystallization. The 40°<111> relation is not established between the {110}<112> rolling texture and the {110}<001> recrystallization texture. The differences are attributed to differences in the stacking fault energies of the materials. The phenomena can be explained by defects that dominates the stored energy of the rolled materials. When the grain boundary energy dominates the stored energy, the {236}<385> texture evolves after recrystallization. On the other hand, when dislocation energy dominates the stored energy, the {110}<001> texture evolves after recrystallization. The {110}<001> recrystallization texture evolution is well explained by the strain-energy-release-maximization theory. The 40°<111> relation is believed to originate in the maximum mobility of <111> tilt boundaries at a rotation angle of 40°.