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High strength and high toughness, and corrosion resistance of Al-Zn-Mg-Cu-based high-performance aluminum slab is the key structural material indispensable in the field of modern aerospace, aviation, military equipment and civilian facilities. Existing equipment conditions, the traditional processing method is difficult to make the aluminum alloy to be fully variable row, so it is difficult to achieve the organization refinement and uniformity of the aluminum alloy plate, and to forging the large deformation within the material can effectively prevent the organization structure, without power and special equipment, so after a broad application prospects. In this paper, a new type of Al-Zn-Mg-Cu high strength aluminum alloy for the study of the thermal deformation mechanical properties and microstructural evolution, upsetting and stretching deformation on microstructure evolution law and granular relatively recrystallization process Finally, the impact, of Al-of Zn-Mg-Cu of high strength aluminum alloy thick plate more than the forging process optimization, specific research content and results: 1 Gleeble-1500D thermal simulation testing machine, the new Al-Zn -Mg-Cu high strength aluminum alloy during deformation process simulation, 250 ℃ ~ 420 ℃ deformation temperature range 0.01 s-1 to 1s-1 strain rate, and 20% to 80% of the amount of deformation within the microstructure evolution. To obtain the optimal process parameters, and provide theoretical support for the formulation of multi-directional forging process. 2 upsetting and stretching deformation on microstructure evolution in high strength aluminum alloy during hot deformation, the study results show that the ratio of the same forging, the the upsetting deformation of strain is lower deformation uneven fine organization of the effect is not obvious; stretching deformation strain and the strain distribution is uniform. Stretching organizations large deformation, thinning effect is obvious. The results of this study provides a theoretical basis for multi-directional forging process upsetting and stretching forging allocation. 3, granular second relatively new type of Al-Zn-Mg-Cu high strength aluminum alloy recrystallization process. Able to play due to a particle size larger than 1μm particle stimulated nucleation so as to promote the role of recrystallization, at the same time to meet the particle excitations the nucleation criterion Fv / r lt; 0.2, so the design of 470 ℃ / 2h solid solution of 400 ° C / 8h timeliness and 400 ° C (8h, 10h, 12h, 14h, 16h) direct aging precipitation for two experimental program to meet the conditions of large-size particles contrast, comparative results show that the second phase particles meet 400 ℃ 12h aging particle stimulated nucleation criterion. After the heat-treated samples after upsetting 50% contrast organization to see the organization under 400 ℃ 12h aging is the most refined, so to determine the optimum heat treatment of 400 ° C 12h. 4, according to the determined heat treatment 400 ° C 12h forging temperature 420 ℃, strain rate of 0.01 s-1, and stretching forging ratio greater than upsetting forging than the deformation of high strength aluminum alloys, Al-Zn-Mg-Cu thick The board multi-forging process optimization. Deform simulation results show that the sample heart strain can reach 9.5, most regions equivalent strain above 7, and more evenly distributed.
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