RESEARCH PAPER |
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Microstructure and Mechanical Properties of 7075 Al Alloy Processed by Combined Cold-rolling and T6 Heat-treatment |
CUI Xinwei, XU Xiaofeng, NING Yuheng, ZHAO Yuguang
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College of Materials Science and Engineering, Jilin University, Changchun 130025; |
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Abstract In order to examine the combined effect of plastic deformation and the T6 treatment on Al-Zn-Mg-Cu alloys, a 7075 Al alloy was subjected to cold-rolling (CR) deformation and T6 heat-treatment (T6) in two different routes of CR+T6 (CR followed with T6) and T6+CR (T6 treatment followed with CR), respectively, and characterized by optical microscopy, transmission electron microscope, and mechanical tensile property measurement. The results show that the cold-rolling before T6 heat treatment has less influences on the tensile strength and elongation of the CR+T6 samples. While the yield strength and ultimate tensile strength of T6+CR samples are remarkably improved with increasing the deformation, and the T6+40% deformation (the optimized T6+CR) sample exhibits superior strength with adequate plasticity, with less energy consumption compared with the 60% deformation T6 sample (the optimized CR+T6). Microstructure investigation reveals that the grain-boundary strengthening and dislocation streng-thening are the primary reasons for the improved mechanical properties of CR+T6 and T6+CR samples.
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Published: 25 July 2017
Online: 2018-05-04
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1 Wu Y,Wen T,Zhu Z T. Development of research and application of aging treatment technology on 7xxx series aluminum alloys[J]. Mater Rev:Rev,2012,26(8):114(in Chinese). 吴颖,温彤,朱曾涛. 7xxx系铝合金时效处理的研究现状及应用进展[J]. 材料导报:综述篇,2012,26(8):114. 2 Song Y,Yang X Q,Cui L,et al.Defect features and mechanical pro-perties of friction stir lap welded dissimilar AA2024-AA7075 aluminum alloy sheets [J]. Mater Des,2014,55(55):9. 3 Wu H P,Wang Z X,Ma Y L,et al. Root cause for lighted structure on the cross section of rolled 5182 aluminum alloy plate [J]. J Chongqing University of Technology:Nat Sci,2017,31(4):58(in Chinese). 吴海鹏,王正曦,麻彦龙,等. 5182铝合金轧制板材截面亮线组织形成机理研究[J].重庆理工大学学报:自然科学,2017,31(4):58. 4 Shaeri M H,Salehi M T,Seyyedein S H,et al.Microstructure and mechanical properties of Al-7075 alloy processed by equal channel angular pressing combined with aging treatment [J]. Mater Des,2014,57(5):250. 5 Naimi A,Yousfi H,Trari M. Influence of cold rolling degree and ageing treatments on the precipitation hardening of 2024 and 7075 alloys [J]. Mechan Time-Dependent Mater,2013,17(3):285. 6 Ma K,Wen H,Hu T,et al. Mechanical behavior and strengthening mechanisms in ultrafine grain precipitation-strengthened aluminum alloy [J]. Acta Mater,2014,62(5):141. 7 Estrin Y,Vinogradov A. Extreme grain refinement by severe plastic deformation: A wealth of challenging science [J]. Acta Mater,2013,61(3):782. 8 Zhu R F,Liu J N,Tang G Y,et al. Properties,microstructure and texture evolution of cold rolled Cu strips under electropulsing treatment [J]. J Alloys Compd,2012,544(24):203. 9 Panigrahi S K,Jayaganthan R. Development of ultrafine grained high strength age hardenable Al 7075 alloy by cryorolling [J]. Mater Des,2011,32(6):3150. 10 Eddahbi M,Jimenez J A,Ruano O A. Microstructure and creep behaviour of an Osprey processed and extruded Al-Cu-Mg-Ti-Ag alloy [J]. J Alloys Compd,2007,433:97. 11 Viana F,Pinto A M P,Santos H M C,et al. Retrogression and re-ageing of 7075 aluminium alloy: Microstructural characterization [J]. J Mater Process Technol,1999,92(99):54. 12 Bydogan M,et al. Improved resistance to stress-corrosion-cracking failures via optimized retrogression and reaging of 7075-T6 aluminum sheets [J]. Metall Mater Trans A,2008,39(39):2470. 13 Liu X Y,Pan Q L,Lu Z L,et al. Effects of solution treatment on the microstructure and mechanical properties of Al-Cu-Mg-Ag alloy [J]. Mater Des,2010,31:4392. 14 Tajally M,Huda Z,Masjuki H H. Effect of deformation and recrystallization conditions on tensile behavior of aluminum alloy 7075 [J]. Metal Sci Heat Treatment,2011,53(3):165. 15 Jian H G,Jiang F,Xu Z Y,et al. Study progress of high strength and tenacity Al-Zn-Mg-Cu aluminum alloy for aviation [J]. Mater Heat Treatment,2006,35(12):61(in Chinese). 蹇海根,姜锋,徐忠艳,等. 航空用高强韧Al-Zn-Mg-Cu系铝合金的研究进展[J].热加工工艺,2006,35(12):61 16 Rao A C U,Vasu V,Govindaraju M,et al. Influence of cold rolling and annealing on the tensile properties of aluminum 7075 alloy [J]. Procedia Mater Sci,2014,5:86. 17 Wang D,Ma Z Y. Effects of rolling process on microstructure and mechanical property of 7075 aluminum alloy [J]. Acta Metall Sin,2008,44(1):49(in Chinese). 王东,马宗义. 轧制工艺对7050铝合金显微组织和力学性能的影响[J].金属学报,2008,44(1):49. 18 Cheng S,Zhao Y H,Zhu Y T,et al. Optimizing the strength and ductility of fine structured 2024 Al alloy by nano-precipitation [J]. Acta Mater,2007,55(17):5822. 19 Somekawa H,Mukai T. Hall-Petch relation for deformation twinning in solid solution magnesium alloys [J]. Mater Sci Eng A,2013,561:378. 20 Zhu Y H,Jiang J,Xiao Y K,et al. Electropulsing-induced microstructure evolution and its effect on electrical conductivity of (Bi0.25-Sb0.75)2Te3 thin films [J]. Scripta Mater,2013,69(3):219. 21 Zheng R,Sun Y,Ametama K,et al. Optimizing the strength and ductility of spark plasma sintered Al 2024 alloy by conventional thermo-mechanical treatment [J]. Mater Sci Eng A,2013,590(1):147. 22 Zhao Y L,Yang Z Q,et al. Double-peak age strengthening of cold-worked 2024 aluminum alloy [J]. Acta Mater,2013,61(5):1624. |
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