Evolution of the microstructures in a DC-cast AA3003 alloy during heat treatment

摘要

The evolution of the primary particles and dispersoids in a D.C-cast 3003 alloy during heat treatment has been quantitatively studied by TEM and SEM. During heating, different heating rates lead to about the same number density of dispersoids at homog-enization temperature, although low heating rate leads to a high number density at low temperatures. During homogenization at high temperatures, the coarsening between the fine dispersoids and coarse primary particles takes a key role in the evolution of the dispersoids. No nucleation of new dispersoids has been found during the cooling process - after homogenization. The 3-D morphology of the primary particles has been revealed by a buta-nol dissolution method. The evolution of the size, composition, fraction and phase transformation of the primary particles during heat treatment has been quantitatively studied.