Abstract：7075 aluminum alloy ingot was prepared by spray forming process, and the material was sequently processed by forging and peak aging heat treatment. Then the mechanical properties of the material in different conditions were tested, the microstructures and tensile fractures were observed. The test results show that the microstructures of spray-formed 7075 aluminum alloy are equiaxed grains, and the size is fine and uniform. The second phase is distributes not only along the grain boundary but also inside the grains with a large number of acicular and spherical shapes. There are some small pores in the spray-formed material. The distribution of Mg and Zn is more uniform, and the segregation is significantly decreased. In the fracture surface of the spray formed material, a river pattern is fand, and it belongs to brittle fracture. After the densification by plastic deformation, the tensile strength is increased to 529 MPa. Moreover, T6 heat treatment can further improve the mechanical properties of spray-formed 7075 aluminum alloy, the tensile strength can be increased to 642 MPa, and the elongation is improved to 8.36%.
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2019, Vol. 24 
