冷間引抜加工を与えたUの性質, (II)

Abstract

In the present work, some characteristics of thermal cycling growth of as cold worked specimens were investigated. As described in the previous report, the direction of growth in recrystallized specimens is the drawing one regardless of working degree. While, the direction of growth in as-worked specimens is dependent upon the working degree. In less than about 11% reduction in area, it is a radial direction. So, when recrystallization proceeds during thermal cycling, the elongation in drawing direction was observed after the initial contraction. The author considered these characteristics of as-worked specimens in connection with the preferred orientation. Namely, it was assumed that main preferred orientation was due to the slip rotation of {010} pole toward the radial direction in less than about 11%, and twinned orientation of {010} pole to the drawing direction occured by {130} and {172} types was gradually increased with increasing working degree so as to prevail over the former near 11%. The change in the direction of growth from the radial to the drawing with increasing working degree was well explained by the above assumption. Some interesting behaviors of twin on recrystallization were also observed as an important clue to solve the formation of the preferred orientation after annealing.