Abstract: Effects of intermediate annealing temperature and cold deformation on the microstructure and properties of 3003 aluminum alloy plate for power battery shell were studied by means of muffle furnace, Brinell hardness tester, optical microscope and universal testing machine. The results show that with the increase of intermediate annealing temperature, the hardness, tensile strength and yield strength of the 3003 aluminum alloy plate with different cold deformation amounts decrease first, and then become stable at 380 ℃ and over, while the elongation is on the contrary. When the annealing temperature is at 200 ℃ and lower, both the strength of the alloy plate increases with the increase of cold deformation. With the increase of annealing temperature, the conductivity of the 3003 aluminum alloy plate increases slowly firstly, then stabilizes, and finally decreases rapidly. When the cold deformation amount is 85%, the conductivity of the alloy is the highest, while it decreases significantly when the cold deformation amount is 95%. The microstructure of the alloy plate changes from slender fiber to fine equiaxed recrystallized grains with the increase of annealing temperature. The greater the cold deformation, the lower the temperature at which the material begins to recrystallize and the finer the recrystallized grains, and the recrystallization is completed at 380 ℃. Overall, the optimal intermediate annealing temperature of the 3003 aluminum alloy plate for power battery shells is 380 ℃, and the optimal cold deformation is 85%.

Key words: power battery shell, 3003 aluminum alloy plate, annealing temperature, microstructure, properties