采用拉伸试验、晶间腐蚀实验、透射电镜观察等方法，研究时效工艺对7A85铝合金显微组织、力学性能和晶间腐蚀行为的影响。结果表明：7A85铝合金的T6态晶内分布着大量细小而弥散的GP区和少量η′相，晶界上析出相(η相)连续分布，无明显的无沉淀析出带(PFZ)；T73态晶内析出相尺寸和间距都变大，晶界析出相长大粗化、呈不连续分布，PFZ带宽化，具有良好的抗晶间腐蚀性能，但强度略低；回归再时效处理后的7A85铝合金具有与 T6态相似的晶内组织和与 T73态相似的晶界组织，合金的抗拉强度及电导率分别为731.7MPa 和36.5%(IACS)，即合金同时具有较好的强度和抗腐蚀性能。合金的晶间腐蚀敏感性与晶界析出相和无沉淀析出带有关，晶界析出相尺寸越大，分布越不连续，PFZ 越宽，合金腐蚀敏感性越小。
The influence of aging process on mechanical properties and intergranular corrosion of 7A85 aluminum alloy wasinvestigated by tensile testing and intergranular corrosion testingcombining with transmission electron microscope. The results show that,a large quantity of GP zones and someη′phasesdisperse in grain, with continuous secondary phases in grain boundary, and the precipitation free zone(PFZ)doesnot exist in the T6 temper.7A85 aluminum obtains a favorable corrosion propertywith the phases inthegrain boundary becomingdiscontinuous and PFZ widening in the T73 temper. 7A85-RRA, which has the T6-like grain-interior and the T73-like grain-boundary morphology, shows good comprehensive performance, withthe combinations of tensile strength of 731.7 MPa and electrical conductivity of 36.5%(IACS). Corrosion sensibility of alloy is related to the characteristics of equilibrium phase and precipitation free zone at grain boundary, with the equilibrium phases discontinuous and PFZ widening, the corrosion sensibility of alloy decreases.
参考文献
| [1] | Tolga Dursun;Costas Soutis.Recent developments in advanced aircraft aluminium alloys[J].Materials & design,2014Apr.(Apr.):862-871. |
| [2] | 刘兵;彭超群;王日初;王小锋;李婷婷.大飞机用铝合金的研究现状及展望[J].中国有色金属学报,2010(9):1705-1715. |
| [3] | Zainul Huda;Prasetyo Edi.Materials selection in design of structures and engines of supersonic aircrafts: A review[J].Materials & design,2013Apr.(Apr.):552-560. |
| [4] | Paul A.ROMETSCH;Yong ZHANG;Steven KNIGHT.7xxx系铝合金热处理的进展[J].中国有色金属学报（英文版）,2014(07):2003-2017. |
| [5] | 王建国;王祝堂.航空航天变形铝合金的进展（3）[J].轻合金加工技术,2013(10):1-14. |
| [6] | 金骥戎;宋仁国;代春丽;王超;李海;祁星;祁文娟.时效、阴极极化对7050铝合金应力腐蚀敏感性的影响[J].材料热处理学报,2015(3):90-95. |
| [7] | 陈送义;陈康华;董朋轩;叶升平;黄兰萍.热处理对7085铝合金应力腐蚀开裂、断裂韧性和强度的影响[J].中国有色金属学报（英文版）,2014(7):2320-2325. |
| [8] | J.T. Jiang;W.Q. Xiao;L. Yang;W.Z. Shao;S.J. Yuan;L. Zhen.Ageing behavior and stress corrosion cracking resistance of a non-isothermally aged Al-Zn-Mg-Cu alloy[J].Materials Science & Engineering, A. Structural Materials: Properties, Misrostructure and Processing,2014:167-175. |
| [9] | LI Hongying;GENG Jinfeng;DONG Xianjuan;WANG Changjian;ZHENG Feng.Effect of Aging on Fracture Toughness and Stress Corrosion Cracking Resistance of Forged 7475 Aluminum Alloy[J].武汉理工大学学报（材料科学版）（英文版）,2007(02):191-195. |
| [10] | 张新明;李鹏辉;刘胜胆;李国锋;朱航飞;周新伟.回归时间对7050铝合金晶间腐蚀性能的影响[J].中国有色金属学报,2008(10):1795-1801. |
| [11] | 姚晓红;张林;高文理;田林海.时效状态对7A85高强铝合金力学性能和晶间腐蚀性能的影响[J].稀有金属材料与工程,2013(12):2581-2585. |
| [12] | 何正林;高文理;陆政;冯朝辉.热处理对7A85铝合金组织和性能的影响[J].材料工程,2015(8):13-18. |
| [13] | J.Z. Liu;J.H. Chen;X.B. Yang;S. Ren;C.L. Wu;H.Y. Xu;J. Zou.Revisiting the precipitation sequence in Al–Zn–Mg-based alloys by high-resolution transmission electron microscopy[J].Scripta materialia,201011(11):1061-1064. |
| [14] | 宁爱林 .析出相及其分布对高强铝合金力学性能的影响[D].中南大学,2007. |
| [15] | 尹志民;方家芳;黄继武;聂波;单长智;郭加林;王琳.时效工艺对7A52铝合金晶间腐蚀和剥蚀行为的影响[J].中南大学学报（自然科学版）,2007(4):617-622. |
| [16] | 刘忠民;蒋金龙.铝制换热器的耐腐蚀性探讨[J].电器,2012(z1):268-275. |
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