微量Cl<sup>-</sup>和温度对7150-T76铝合金电化学腐蚀性能的影响

doi:10.11902/1005.4537.2015.051

中国腐蚀与防护学报

2016, Vol. 36

Issue (2): 121-129 DOI: 10.11902/1005.4537.2015.051

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微量Cl^-和温度对7150-T76铝合金电化学腐蚀性能的影响

孙擎擎^1,^2,³,周文辉¹,谢跃煌²,董朋轩²,陈康华²,陈启元¹(

)

1. 中南大学有色金属资源化学教育部重点实验室长沙 410083
2. 中南大学粉末冶金国家重点实验室长沙 410083
3. Purdue University School of Chemical Engineering West Lafayette 47906

Effect of Trace Chloride and Temperature on Electrochemical Corrosion Behavior of 7150-T76 Al Alloy

Qingqing SUN^1,^2,³,Wenhui ZHOU¹,Yuehuang XIE²,Pengxuan DONG²,Kanghua CHEN²,Qiyuan CHEN¹(

)

1. Key Laboratory of Resource Chemistry of Nonferrous Metals, Ministry of Education, Central South University, Changsha 410083, China
2. State Key Laboratory of Powder Metallurgy, Central South University, Changsha 410083, China
3. School of Chemical Engineering, Purdue University, West Lafayette 47906, USA

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摘要:

利用开路电位、循环极化法和腐蚀形貌表征研究了微量Cl^-与温度对7150-T76超高强度铝合金电化学腐蚀性能的影响。结果表明：低温低Cl^-浓度的溶液中,铝合金主要发生点蚀;温度升高、Cl^-浓度增大,晶间腐蚀的倾向逐渐变大。微量Cl^-(20 mmol/L) 致使开路电位 (OCP) 显著负移;温度升高OCP逐渐降低,且在60~70 ℃温度范围内发生突变,表明腐蚀机理发生变化。还分析了循环极化曲线的各个电位和电流密度参数随Cl^-浓度和温度的变化。点蚀转换电位E_ptp的出现表明被侵蚀后的铝合金表面的钝化是分步进行的,E_ptp随Cl^-浓度的增大逐渐负移。自腐蚀电流密度随温度的升高先增大再减小,而自腐蚀电位逐渐负移,均可归因于高温溶液中溶解氧减少的缘故。此外,也论证了自腐蚀电位和再钝化电位的差值ΔE₃(E_corr-E_rep) 作为评价局部腐蚀发展程度标准的局限性。

关键词 ： 7150铝合金, 微量Cl-, 温度, 循环极化曲线, 电位参数

Abstract：

3.5%(mass fraction) NaCl has been intensively used as an electrolyte for evaluating the corrosion behavior Al-alloys for decades due to the simulated sea water being close to the real service environment, particularly for the carrier-based aircrafts. But this medium has several limitations such as the lack of acid substances and the absence of pitting potentials in polarization curves for some alloys. According to Arrhenius equation, the corrosion rate is promoted by temperature. In fact, one of the most crucial factors in the corrosion of Al alloys is temperature which has a strong impact on the stability and properties of passive films. In the present work, the influence of trace Cl^- and temperature on the electrochemical corrosion of 7150-T76 Al alloy was investigated by measurements of open circuit potentials (OCP) and cyclic polarization curves as well as observation of corrosion morphology. The results showed that the localized corrosion of 7150 Al alloy was promoted by the increase of Cl^- concentration and temperature. In the solutions with relatively low temperature and low chloride concentration, pitting corrosion was the main corrosion form, while for higher temperature and higher chloride concentration, the corrosion of the alloy gradually turned to be intergranular corrosion. The presence of pit transition potential E_ptp reflects a step-wise propagation of corrosion on very narrow fronts with a sequence of active tip-passive walls. OCP shifts to the negative direction with the increase of Cl^- concentration and temperature, respectively. Moreover, OCP decreased drastically with increasing temperature above 60 ℃, indicating the chan-ge of corrosion mechanism in the temperature range from 60 to 70 ℃. In the medium of 0.1 mol/L Na₂SO₄+1 mmol/L NaCl, the free corrosion potential decreased, while the free corrosion current density increased firstly and then decreased with the increase of temperature due to less dissolved oxygen at higher temperatures. Differences between potential parameters such as ΔE₁(E_pit-E_corr), ΔE₂ (E_corr-E_ptp) and ΔE₃(E_corr-E_rep) were determined as criteria to assess localized corrosion. The value of ΔE₃(E_corr-E_rep) increased linearly with the increase of Cl^- concentration. However, ΔE₃ showed a turning point at 70 ℃ because uniform corrosion occurred at 80 ℃ as deduced from corrosion morphology. It can be concluded that ΔE₃(E_corr-E_rep) only increases linearly with the corrosion propagation at the first stage of localized corrosion.

Key words： 7150 Al alloy trace Cl- temperature cyclic polarization potential parameter

基金资助:国家自然科学基金重点项目 (51134007) 和国家重大科研仪器设备研制专项项目 (51327902) 资助

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引用本文:

孙擎擎,周文辉,谢跃煌,董朋轩,陈康华,陈启元. 微量Cl^-和温度对7150-T76铝合金电化学腐蚀性能的影响[J]. 中国腐蚀与防护学报, 2016, 36(2): 121-129.
Qingqing SUN, Wenhui ZHOU, Yuehuang XIE, Pengxuan DONG, Kanghua CHEN, Qiyuan CHEN. Effect of Trace Chloride and Temperature on Electrochemical Corrosion Behavior of 7150-T76 Al Alloy. Journal of Chinese Society for Corrosion and protection, 2016, 36(2): 121-129.

链接本文:

https://www.jcscp.org/CN/10.11902/1005.4537.2015.051 或 https://www.jcscp.org/CN/Y2016/V36/I2/121

图1 7150铝合金在含不同Cl-浓度的电介质中的开路电位-时间曲线

图2 7150铝合金在3.5%NaCl溶液中的循环极化曲线

图3 7150铝合金在含不同Cl-浓度的电介质中的循环极化曲线

图4 电流密度和线性极化电阻随Cl-浓度的变化

图5 不同电位随Cl-浓度的变化

图6 不同电位差随Cl-浓度的变化

图7 铝合金试样在含不同Cl-浓度介质中循环极化后的腐蚀形貌

图8 7150铝合金在不同温度下的0.1 mol/L Na2SO4+1 mmol/L NaCl溶液中的OCP-时间曲线

图9 7150铝合金在不同温度下的0.1 mol/L Na2SO4+1 mmol/L NaCl溶液中的循环极化曲线

图10 电流密度和线性极化电阻随温度的变化

图11 电位及电位差随温度的变化曲线

图12 7150铝合金在不同温度下的0.1 mol/L Na2SO4+1 mmol/L NaCl溶液中循环极化后的腐蚀形貌

[1]	Heinz A, Haszler A, Keidel C, et al.Recent development in aluminium alloys for aerospace applications[J]. Mater. Sci. Eng., 2000, A280(1): 102
[2]	Chen K H, Liu H W, Liu Y Z.Effect of promotively-solutionizing heat treatment on the mechanical properties and fracture behavior of Al-Zn-Mg-Cu alloys[J]. Acta Metall. Sin., 2001, 37(1): 29
[2]	(陈康华, 刘红卫, 刘允中. 强化固溶对Al-Zn-Mg-Cu合金力学性能和断裂行为的影响[J]. 金属学报, 2001, 37(1): 29)
[3]	Zhang X M, Li P H, Liu S D, et al.Effect of retrogression time on intergranular corrosion of 7050 aluminum alloy[J]. Chin. J. Nonferrous Met., 2008, 18(10): 1795
[3]	(张新明, 李鹏辉, 刘胜胆等. 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, 18(10): 1795)
[4]	Cao C N.Principles of Corrosion Electrochemistry [M]. Beijing: Chemical Industry Press, 2004: 276
[4]	(曹楚南. 腐蚀电化学原理 [M]. 北京: 化学工业出版社, 2004: 276)
[5]	Wloka J, Virtanen S.Influence of scandium on the pitting behaviour of Al-Zn-Mg-Cu alloys[J]. Acta Mater., 2007, 55(19): 6666
[6]	Sun Q Q, Dong P X, Sun R J, et al.Effect of ageing process on electrochemical corrosion property of Al-6.2Zn-2.3Mg-2.3Cu aluminium alloy[J]. Chin. J. Nonferrous Met., 2015, 25(4): 866
[6]	(孙擎擎, 董朋轩, 孙睿吉等. 时效制度对挤压Al6.2Zn2.3Mg2.3Cu铝合金电化学腐蚀性能的影响[J]. 中国有色金属学报, 2015, 25(4): 866)
[7]	Meng Q, Frankel G.Effect of Cu content on corrosion behavior of 7xxx series aluminum alloys[J]. J. Electrochem. Soc., 2004, 151(5): B271
[8]	Yasuda M, Weinberg F, Tromans D.Pitting corrosion of Al and Al-Cu single crystals[J]. J. Electrochem. Soc., 1990, 137(12): 3708
[9]	Finšgar M, Milošev I.Corrosion behaviour of stainless steels in aqueous solutions of methanesulfonic acid[J]. Corros. Sci., 2010, 52(7): 2430
[10]	Pickering H W.On the roles of corrosion products in local cell processes[J]. Corrosion, 1986, 42(3): 125
[11]	Trueba M, Trasatti S P.Study of Al alloy corrosion in neutral NaCl by the pitting scan technique[J]. Mater. Chem. Phys., 2010, 121(3): 523
[12]	Cicolin D, Trueba M, Trasatti S.Effect of chloride concentration, pH and dissolved oxygen, on the repassivation of 6082-T6 Al alloy[J]. Electrochim. Acta, 2014, 124: 27
[13]	Comotti I M, Trueba M, Trasatti S P.The pit transition potential in the repassivation of aluminium alloys[J]. Surf. Interface Anal., 2013, 45(10): 1575
[14]	Trdan U, Grum J.Evaluation of corrosion resistance of AA6082-T651 aluminium alloy after laser shock peening by means of cyclic polarisation and ElS methods[J]. Corros. Sci., 2012, 59: 324
[15]	Pride S, Scully J, Hudson J.Metastable pitting of aluminum and criteria for the transition to stable pit growth[J]. J. Electrochem. Soc., 1994, 141(11): 3028
[16]	Ezuber H, El-Houd A, El-Shawesh F.A study on the corrosion behavior of aluminum alloys in seawater[J]. Mater. Des., 2008, 29(4): 801
[17]	Soltis J, Laycock N, Krouse D.Temperature dependence of the pitting potential of high purity aluminium in chloride containing solutions[J]. Corros. Sci., 2011, 53(1): 7
[18]	Li J F, Birbilis N, Li C X, et al.Influence of retrogression temperature and time on the mechanical properties and exfoliation corrosion behavior of aluminium alloy AA7150[J]. Mater. Charact., 2009, 60(11): 1334

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