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A new process consisting of the spray forming and the continuous extrusion forming for manufacturing 7075Al alloy was proposed.The microstructure evolution,mechanical properties and the resistance to stress corrosion cracking of the alloy were studied.The results indicate that the spray forming process induces obviously grain refinement and greatly lower segregation microstructure.Besides,the Conform process produces finer grains and conduces to more uniform distribution of the precipitates of Al Cu and MgZn_2 phases.The fabricated alloy shows good comprehensive mechanical properties and superb performance of stress corrosion resistance.Moreover,a better combination of the mechanical properties and the resistance to stress corrosion cracking could then be obtained under a certain condition of atomization gas pressure of 0.19 MPa.The enhanced properties are attributed to the following factors,which include the grain refinement,the fine and homogeneous distribution of Al Cu and MgZn_2 phases,the high density of the extruded products,as well as the discontinuous distribution of the grain boundaries after retrogression and reaging(RRA)heat treatment.
A new process consisting of the spray forming and the continuous extrusion forming for manufacturing 7075Al alloy was proposed. Microstructure evolution, mechanical properties and the resistance to stress corrosion cracking of the alloy were studied. The results indicate that the spray forming process induces obviously grain. refinement and greatly lower segregation microstructure.Besides, the Conform process produces finer grains and conduces to more uniform distribution of the precipitates of Al Cu and MgZn 2 phases. fabricated alloys shows good overall mechanical properties and superb performance of stress corrosion resistance. Moreover, a better combination of the mechanical properties and the resistance to stress corrosion cracking could then be obtained under certain conditions of atomization gas pressure of 0.19 MPa.The enhanced properties are attributed to the following factors, which include the grain refinement, the fine and homogeneous distribution of Al Cu and MgZn_2 ph ases, the high density of the extruded products, as well as the discontinuous distribution of the grain boundaries after retrogression and reaging (RRA) heat treatment.