RECRYSTALLIZATION IN COLD-ROLLED PURE NICKEL

Electrolytic nickel sheets with different grain sizes, 0. 02 and 0. 2 mm, were straight-rolled to 99% mainly at room temperature and annealed. The rolling texure and primary and secondary recrystallization textures were measured by X-ray diffraction and selected area channeling pattern methods. As rolled samples showed the copper type texture independent of initial grain size. After annealing at 573 K, primary recrystallization was completed. The recrystallization texture of the fine grained sample showed a cube orientation, while that of the coarse grained sample took a diffuse cube orientation. With increasing annealing temperature the primary recrystallization texture of both samples became a sharp cube orientation. Secondary recrystallization occurred during annealing at 1273 K for the coarse grained sample and at 1573 K for the fine grained sample. Most of the orientations of secondary-recrystallized grains are related to the primary recrystallization cube texture, left brace 001 right brace LT AN BR 100 RT AN BR ; rotation around 22 degree (0. 384 rad) or 38 degree (0. 663 rad) about a LT AN BR 111 RT AN BR axis and 19 degree (0. 331 rad) about a LT AN BR 100 RT AN BR axis.