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The 7005 aluminum alloy is Al-Zn-Mg-based can be heat treated to strengthen the aluminum alloy, the alloy has a good heat deformation properties, and a wide range of quenching, by appropriate heat treatment process, the alloy may reach a higher strength. 7005 aluminum alloy also has good weldability, is a high strength weldable aluminum alloy, but also has a certain amount of stress corrosion tendency. Homogenizing annealing aluminum alloy segregation of coarse second phase sufficiently melting or transformation can be effective in improving the alloy cold, heat distortion performance, reducing the danger of cracking of the hot rolling of the alloy. This paper studies the homogenization annealing of 7005 aluminum alloy and performance to explore the 7005 aluminum alloy homogenization annealing process, through research the following conclusions: the homogenizing annealing can effectively eliminate alloy casting process of the formation of the second phase, the elimination of the dendritic segregation, greatly reducing the volume fraction of the second phase in the alloy, the alloy structure more uniform; homogenizing annealing after 460 ℃ × 24h after the second phase in the alloy does not fully melted, the alloy still There are a large number of the second phase is present, homogenizing annealing after 470 ℃ × 24h after a second phase of the alloy further melting into the matrix, after 480 ℃ × 24h after the homogenizing annealing the alloy with different degrees of organization of the complex melt, alloys appeared burned, therefore, the 7005 aluminum alloy homogenization temperature does not exceed 480 ° C annealing. Homogenizing annealing well improve the distribution of the main alloying elements in the alloy, so that the major alloying elements diffusion to the grain by grain boundaries, to achieve the homogenization of the major alloying elements. 7005 aluminum alloy in the main alloying elements Zn, Mg in the solidification process easily the form of a second phase present in the alloy, these second phase crowded out in the grain boundary, leading to the main alloying elements Zn, the distribution of Mg imbalance, performance at the grain boundaries Zn, Mg content is much higher than the substrate, homogenizing annealing, the main alloying element with the dissolution of the second phase, by diffusion, to achieve a main alloying element tends to be uniform. The homogenizing annealing effectively improve the mechanical properties of the alloy, in particular to improve the ductility of the alloy. 7005 aluminum alloy Ti-containing cast due to the fine grain aluminum ingots refining alloy is more uniform than the Al-10Ti alloy refinement organization, and this organization homogenizing annealing process is effective inherited fine grain refinement of aluminum ingot aluminum alloy 7005 after 460 ℃ × 24h homogenizing annealing can be achieved by good plasticity. Of 7005 aluminum alloy containing Sc, Ti, Sc, Zr joint refinement of the alloy has a more uniform cast structure, changes in the mechanical properties of alloy homogenized before and after annealing. Ti added greatly improve the ductility of the alloy the SC added can greatly enhance the strength of the alloy, Ti, Sc, Zr, joint refinement alloy having the best strength, by fine ingots refining alloy has the best plasticity .
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