Stretch rate and deformation for pre-stretching aluminum alloy sheet

Abstract

Numerical simulation combined with experimental test was carried out to analyze the pre-stretching process of the 7075 aluminum alloy sheet, from which the stress variation curves and residual stress of aluminum alloy sheet in different stretch rates were obtained. The results show that the residual stress in length direction is released after unloading the stretch force, while the residual stress in width direction is released during the stretching process. The study of residual stress elimination is beneficial for optimizing stretch rate on the basis of residual stress distribution law. By comparing the variation principle of residual stress in length direction, the size range of three deformation areas and elimination percentage of residual stress were obtained. The residual stresses of clamping area and transition area are not eliminated effectively, so sawing quantity should be the sum of both the areas. The elimination rate of residual stress in even deformation area could reach 90% after choosing a proper stretch rate, which is verified by both simulation and experiment.

Keywords

residual stress / stretch rate / deformation area / sawing quantity

References

[1] TannerD. A., RobinsonJ. S.. Reducing residual stress in 2014 aluminium alloy die forgings [J]. Materials & Design, 2008, 29(7): 1489-1496

[2] TannerD. A., RobinsonJ. S.. Residual stress magnitudes and related properties in quenched aluminium alloys [J]. Materials Science and Technology, 2006, 22(1): 77-85

[3] ZhangY.-y., WuY.-x., LiL.-m., ZhangM.-rong.. Finite element simulation of residual stress in pre-stretching thick-plates 0f 7075 aluminum alloy after quenching [J]. Material & Heat Treatment, 2008, 37(14): 88-91

[4] ZhaoL.-l., ZhangY.-du.. FEM simulation for residual stress in quenched aeronautics aluminum alloy thick-plate based on rolled residual stresses distribution [J]. Journal of Beijing University of Aeronautics and Astronautics, 2006, 32(1): 88-91

[5] JeanmartP., BouvaistJ.. Finite element calculation and measurement of thermal stress in quenched plates of high strength 7075 aluminum alloy [J]. Materials Science and Technology, 1985, 1(3): 765-769

[6] NakayamaY., TakaaiT., KimuraS.. Evaluation of surface residual stresses in cold-rolled 5083 aluminum alloy by X-ray method [J]. Mater Trans JIM, 1993, 34(6): 496-503

[7] Rasouli YazdiS., RetraintD., LuJ.. Study of through-thickness residual stress by numerical and experimental techniques [J]. J Strain Analysis, 1998, 33: 449-460

[8] KocM., CulpJ., AltanT.. Prediction of residual stresses in quenched aluminum blocks and their reduction through cold working processes [J]. Journal of Materials Processing Technology, 2006, 174: 342-354

[9] RobinsonJ. S., HossainS., TrumanC. E., ParadowskaA. M., HughesD. J., WimporyR. C., FoxM. E.. Residual stress in 7449 aluminium alloy forgings [J]. Materials Science and Engineering A, 2010, 527: 2603-2612

[10] KesslerO., ReichM.. Similarities and differences in heat treatment simulation of aluminium alloys and steels [J]. Material Science and Engineering Technology, 2009, 40: 473-478

[11] LinG.-y., ZhengX.-y., FengD., YangW., PengD.-shu.. Research development of quenching-induced residual stress of aluminum thick plates [J]. Materials Review, 2008, 22(6): 70-74

[12] GongH., WuY.-x., LiaoKai.. Influence of re-stretching on residual stress distribution in 7075 aluminum alloy thick-plate [J]. Transactions of Materials and Heat Treatment, 2009, 30(6): 201-205

[13] JuijermP., AltenbergerI., ScholtesB.. Fatigue and residual stress relaxation of deep rolled differently aged aluminium alloy AA6110 [J]. Materials Science and Engineering A, 2006, 426: 4-10

[14] ZhuC.-c., LuoJ.-y., LiD.-f., ZhongY., LiYun.. Numerical simulation and experimental investigation of the aluminium alloy quenching-induced residual stress by considering the flow stress characteristic [J]. Journal of Mechanical Engineering, 2010, 46(22): 41-46

[15] LiaoK., WuY.-x., GongHai.. Simulation of deformed area for pre-stretching aluminum alloy thick plates [J]. Transactions of Materials and Heat Treatment, 2009, 30(2): 198-202