Effect of Dispersed Precipitates on Recrystallized Grain Size of 3003 Aluminum Alloy

Regarding the grain coarsening issue of 3003 aluminum alloy cold rolled plate during recrystallization annealing, optical microscopy, scanning electron microscopy(SEM), energy spectrum analysis, X-ray diffraction and transmission electron microscopy were used to investigate the mechanism for the effect of dispersed precipitates, including their kinds, size and distribution on the recrystallization grain size, which were formed during homogenization annealing and intermediate annealing. The results indicate that the recrystallization starting temperature of 3003 aluminum alloy cast-rolling plate is 540 degrees C; the coarse dispersed phases that formed during the homogenization annealing process facilitate the recrystallization, while the fine ones restrain the recrystallization; the fine dispersed phases that formed during the intermediate annealing have a weak effect on the recrystallization; there is no dispersed phases in the plate after intermediate annealing at 500 degrees C for 200s; at this time, recrystallization occurs prior to the precipitate of dispersed phase; there are many fine AlMnSi phase precipitates in the plate after intermediate annealing at 500 degrees C for 2h; the optimum homogenization annealing temperature range of 3003 aluminum alloy is between 560C and 580 degrees C.