Ａｌ‐Ｍｇ系合金薄板のｒ値に及ぼすＭｇ量および中間焼なましの影響

Abstract

Effects of Mg content and intermediate annealing on r-value were studied in Al–Mg alloy sheets with Mg content of 0~7%. In the condition without intermediate annealing, r0 and r90 were higher than r45 in pure aluminum and Al–Mg alloys with Mg content less than 4%, while r45 was higher than r0 and r90 in Al–Mg alloys with Mg content more than 4%. The recrystallization texture was mainly {100} in the former and {310} in the latter. Intermediate annealing with the final cold rolling of about 30% increased r-value and decreased planar anisotropy in Al–Mg alloy sheets. The mean r-value, r, was higher with intermediate annealing than without intermediate annealing, and Mg content dependence of r was minimized with intermediate annealing in Al–Mg alloys with Mg content above 3%. The recrystallization texture was found to be very random and considered to be responsible for such effect of intermediate annealing. Light cold rolling of about 10% after intermediate annealing gave rise to high r with large planar anisotropy. The recrystallization texture was revealed to be {145} , and was regarded to be caused by strain-induced grain boundary migration.