DL-苹果酸对7075铝合金硬质阳极氧化膜结构及耐磨蚀性能的影响

满成; 王孟斐; 颜晴; 吴德权; 崔中雨

doi:10.16490/j.cnki.issn.1001-3660.2025.18.003

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表面技术 ›› 2025, Vol. 54 ›› Issue (18) : 27-36. DOI: 10.16490/j.cnki.issn.1001-3660.2025.18.003

腐蚀与防护

DL-苹果酸对7075铝合金硬质阳极氧化膜结构及耐磨蚀性能的影响

满成^1,*, 王孟斐¹, 颜晴¹, 吴德权^2,*, 崔中雨¹

作者信息 +

Effect of DL-malic Acid on Hard Anodic Film Structure and Wear and Corrosion Resistance of 7075 Aluminum Alloy

MAN Cheng^1,*, WANG Mengfei¹, YAN Qing¹, WU Dequan^2,*, CUI Zhongyu¹

Author information +

文章历史 +

摘要

目的硬质阳极氧化技术常用来提高铝合金的耐磨损腐蚀性能,环保型电解液是硬质阳极氧化技术现阶段的重要发展趋势,选用环保型DL-苹果酸部分替代硫酸,探究DL-苹果酸对7075铝合金硬质阳极氧化膜结构及耐磨蚀性能的影响。方法通过正交试验确定基础溶液成分,以此为基础配制DL苹果酸浓度为20、40、60、80 g/L的电解液,将7075铝合金在不同DL-苹果酸浓度的溶液中进行阳极氧化,通过电化学测量、磨损腐蚀试验,结合扫描电子显微镜、原子力显微镜、X射线光电子能谱等表征手段,系统分析膜层的组织结构、组成成分,探索硬质阳极氧化过程的生长机制。结果研究表明DL-苹果酸浓度为40 g/L时,试样表面形成均匀致密的氧化膜表面,厚度高达47 μm,硬度达351.5 HV0.2,硬度是7075铝合金基材的2倍;7075铝合金阳极氧化膜的成分主要为Al₂O₃、AlOOH,此外还含有一定量的硫酸盐、有机碳。此外,DL-苹果酸浓度为20 g/L溶液中形成的氧化层中检测出结晶态γ-Al₂O₃;阳极氧化后,试样的耐磨蚀性能显著提高,其中膜层具有优异的耐磨性,磨痕深度仅有-3.74 μm,仅为7075铝合金的2%。结论环保型DL-苹果酸在铝合金硬质阳极氧化中能够部分替代硫酸,并且DL-苹果酸能够提高铝合金阳极氧化的成膜效率并增加膜层厚度,可显著提高铝合金的耐磨损腐蚀性能,最终确定最优电解液配比为硫酸200 g/L、草酸 40 g/L、DL-苹果酸40 g/L。

Abstract

Hard anodizing technology is commonly used to enhance the wear and corrosion resistance of aluminum alloys, and eco-friendly electrolytes represent an important development trend in the current stage of this technology. The work aims to choose DL-malic acid as a partial substitute for sulfuric acid to integrate the excellent conductivity properties of sulfuric acid and oxalic acid, and investigate the effect of the DL-malic acid content on the structure and abrasion resistance of the hard anodic film formed on 7075 aluminum alloys. Specifically, the basic solution (200 g/L sulfuric acid +40 g/L oxalic acid) and process parameters ((2±2) ℃, 3 A/dm², 60 min) were firstly determined through an orthogonal test and then the electrolytes with 20 g/L, 40 g/L, 60 g/L, and 80 g/L DL-malic acid were prepared by adding DL-malic acid to the basic solution. Finally, the structure, composition, and performance of the hard anodic film formed on 7075 aluminum alloys in the solutions were characterized through scanning electron microscopy (SEM), atomic force microscopy (AFM), and X-ray photoelectron spectroscopy (XPS). The experimental results revealed that the anodic films were mainly composed by nanoscale oxide particles except some micro pores. Among them, the films formed in the solution with 40 g/L DL-malic acid possessed the smallest particles and least pores. With the DL-malic acid content increasing, the thickness of the anodic film increased initially and decreased afterwards, and inflection point was 40 g/L when the film thickness was 47 μm. The hardness of the anodic film was much larger than that of the matrix, especially the one formed in the condition of 40 g/L DL-malic acid whose hardness was 351.5 HV0.2, about twice of 7075 aluminum alloy. The composition analysis indicated that the oxide film primarily consisted of Al₂O₃ and AlOOH with additional amounts of sulfate and organic carbon. In addition, characteristic peaks related to the crystallographic γ-Al₂O₃ were detected only in the film formed in the electrolyte with DL-malic acid concentration of 20 g/L, confirming the effect of the DL-malic acid on the crystalline structure of the anodic film. The results of the wear corrosion tests indicated that as compared to the base material, the friction coefficients of the anodic film were larger owing to the roughness increasing during the anodic process, while the corrosion potential increased by about 0.58 V, the corrosion density decreased by about two orders of magnitude, and the minimum value (1.949×10^-6 A/cm²) belonged to the films formed in the solution with 40 g/L DL-malic acid. After anodic process, the wear resistance was improved significantly, and the anodic film formed in the condition with 40 g/L DL-malic acid exhibited the best the wear resistance. The polishing scratch was -3.74 μm which was only 2% of that on the surface of 7075 aluminum alloy. The microtopography of the polishing scratch revealed that the wear type of the sample treated in the electrolyte containing 20 g/L DL-malic acid belonged to abrasive wear, and the others were fatigue wear. In summary, DL-malic acid plays a significant role in inhibiting corrosion during the anodizing process, which helps to improve film formation efficiency and increase the thickness of the oxide film, and the optimized electrolyte is made up of 200 g/L sulfuric acid, 40 g/L oxalic acid, and 40 g/L DL-malic acid.

导出引用

满成, 王孟斐, 颜晴, 吴德权, 崔中雨. DL-苹果酸对7075铝合金硬质阳极氧化膜结构及耐磨蚀性能的影响[J]. 表面技术. 2025, 54(18): 27-36 https://doi.org/10.16490/j.cnki.issn.1001-3660.2025.18.003

MAN Cheng, WANG Mengfei, YAN Qing, WU Dequan, CUI Zhongyu. Effect of DL-malic Acid on Hard Anodic Film Structure and Wear and Corrosion Resistance of 7075 Aluminum Alloy[J]. Surface Technology. 2025, 54(18): 27-36 https://doi.org/10.16490/j.cnki.issn.1001-3660.2025.18.003

中图分类号： TG174.4

参考文献

[1] IWASZKO J, KUDŁA K. Surface Remelting Treatment of 7075 Aluminum Alloy—Microstructural and Technological Aspects[J]. Materials Research Express, 2020, 7(1): 016523.
[2] MENG S P, YU Y Q, ZHANG X B, et al.Investigations on Electrochemical Corrosion Behavior of 7075 Aluminum Alloy with Femtosecond Laser Modification[J]. Vacuum, 2024, 221: 112911.
[3] LUO Q S, SHEN J, WANG X D, et al.Microstructure Evolution and Tribo-Oxidation Induced by Friction and Wear of Cast Iron Brake Discs[J]. Surface Science and Technology, 2024, 2(1): 1.
[4] LI Y B, XIE G X, SUN X H, et al.A Review on Fretting Wear/Fatigue Behavior, Protective Measures, and Application Examples of Typical Alloy Materials[J]. Proceedings of the Institution of Mechanical Engineers, Part J: Journal of Engineering Tribology, 2025: 13506501241313249.
[5] WU H, WANG M T, BIAN G X, et al.Comparative Study of Stress Corrosion Cracking and Corrosion-Induced Mechanical Property Degradation of 7050-T7451 Aluminum Alloy in Chloride Solution Containing Bisulfite[J]. Engineering Failure Analysis, 2025, 167: 109054.
[6] CUI Z Y, LI X G, XIAO K, et al.Atmospheric Corrosion Behaviour of Pure Al₁₀₆₀ in Tropical Marine Environment[J]. Corrosion Engineering, Science and Technology, 2015, 50(6): 438-448.
[7] SONG Y W, ZHU M Y, DONG K H, et al.Relationship between the B₄C Reinforcement Content and the Properties of MAO Films on the B₄C/Al Matrix Composites[J]. Surface Science and Technology, 2024, 2(1): 30.
[8] DAVAL J, BRUNOL E, ROUGE N, et al.Oxide Barrier Thinning in 1050, 2024 and 6062 Aluminum Alloys Using Linear Ramp at the End of Sulfuric Anodizing[J]. Journal of the Electrochemical Society, 2025, 172(1): 013508.
[9] SHIN D H, KIM S J.Effects of Hard Anodizing on Mechanical and Electrochemical Characteristics of Aluminum Alloys under Tribocorrosion Condition[J]. Corrosion Science, 2024, 240: 112503.
[10] SANO T, WAKABAYASHI Y, ASOH H.Formation of Hard Anodic Films on the 7075-T6 Aluminum Alloy by Anodization in Sulfuric Acid and Ethylene Glycol[J]. Surface and Coatings Technology, 2023, 459: 129399.
[11] CABRAL-MIRAMONTES J, ALMERAYA-CALDERÓN F, LÓPEZ F E, et al. Citric Acid as an Alternative to Sulfuric Acid for the Hard-Anodizing of AA6061[J]. Metals, 2021, 11(11): 1838.
[12] CABRAL-MIRAMONTES J, ALMERAYA-CALDERÓN F, MÉNDEZ-RAMÍREZ C T, et al. Effect of Citric Acid Hard Anodizing on the Mechanical Properties and Corrosion Resistance of Different Aluminum Alloys[J]. Materials, 2024, 17(17): 4285.
[13] KIKUCHI T, YAMAMOTO T, SUZUKI R O.Growth Behavior of Anodic Porous Alumina Formed in Malic Acid Solution[J]. Applied Surface Science, 2013, 284: 907-913.
[14] VIGNOLI MACHADO T, ATZ DICK P, KNÖRNSCHILD G H, et al. The Effect of Different Carboxylic Acids on the Sulfuric Acid Anodizing of AA2024[J]. Surface and Coatings Technology, 2020, 383: 125283.
[15] CHERNYAKOVA K, KLIMAS V, JAGMINAS A, et al.Features of the Porous Morphology of Anodic Alumina Films at the Initial Stage of Disordered Growth[J]. Electrochemistry Communications, 2022, 143: 107391.
[16] KESHAVARZ A, PARANG Z, NASSERI A.The Effect of Sulfuric Acid, Oxalic Acid, and Their Combination on the Size and Regularity of the Porous Alumina by Anodization[J]. Journal of Nanostructure in Chemistry, 2013, 3(1): 34.
[17] GIOVANARDI R, FONTANESI C, DALLABARBA W.Adsorption of Organic Compounds at the Aluminium Oxide/Aqueous Solution Interface during the Aluminium Anodizing Process[J]. Electrochimica Acta, 2011, 56(9): 3128-3138.
[18] 詹中伟, 孙志华, 葛玉麟. 模拟舰载环境对2124铝合金耐蚀及疲劳性能的影响[J]. 科技导报, 2022, 40(5): 69-77.
ZHAN Z W, SUN Z H, GE Y L.Effect of Shipborne Environment on Corrosion Resistance and Fatigue Property of 2124 Aluminum Alloy[J]. Science & Technology Review, 2022, 40(5): 69-77.
[19] HU X H, GAO K Y, XIONG X Y, et al.Influence of Grain Size and Film Formation Potential on the Diffusivity of Point Defects in the Passive Film of Pure Aluminum in NaCl Solution[J]. Metals, 2024, 14(7): 782.
[20] ZAJĄCZKOWSKA L, SIEMIASZKO D, NOREK M. Towards Self-Organized Anodization of Aluminum in Malic Acid Solutions-New Aspects of Anodization in the Organic Acid[J]. Materials, 2020, 13(17): 3899.
[21] FELIU S, BARTOLOMÉ M J, GONZÁLEZ J A, et al. XPS Characterization of Porous and Sealed Anodic Films on Aluminum Alloys[J]. Journal of the Electrochemical Society, 2007, 154(5): C241.
[22] GAO P H, FU R T, CHEN B Y, et al.Corrosion Resistance of CoCrFeNiMn High Entropy Alloy Coating Prepared through Plasma Transfer Arc Claddings[J]. Metals, 2021, 11(11): 1876.
[23] ZHANG W W, MEI T Y, LI B S, et al.Effect of Current Density and Agitation Modes on the Structural and Corrosion Behavior of Ni/Diamond Composite Coatings[J]. Journal of Materials Research and Technology, 2021, 12: 1473-1485.
[24] GUPTA A, SRIVASTAVA C.Electrodeposition Current Density Induced Texture and Grain Boundary Engineering in Sn Coatings for Enhanced Corrosion Resistance[J]. Corrosion Science, 2022, 194: 109945.
[25] 谢晓伟. 苹果酸-硫酸铝合金硬质阳极氧化工艺研究[D]. 成都: 西华大学, 2022.
XIE X W.Study on hard anodic oxidation process of aluminum alloy malate-sulfate[D]. Chengdu: Xihua University, 2022.
[26] KIM Y S, PYUN S I, MOON S M, et al.The Effects of Applied Potential and pH on the Electrochemical Dissolution of Barrier Layer in Porous Anodic Oxide Film on Pure Aluminium[J]. Corrosion Science, 1996, 38(2): 329-336.
[27] WYSOCKA J, CIESLIK M, KRAKOWIAK S, et al.Carboxylic Acids as Efficient Corrosion Inhibitors of Aluminium Alloys in Alkaline Media[J]. Electrochimica Acta, 2018, 289: 175-192.
[28] LU J Q, WEI G Y, YU Y D, et al.Aluminum Alloy AA2024 Anodized from the Mixed Acid System with Enhanced Mechanical Properties[J]. Surfaces and Interfaces, 2018, 13: 46-50.
[29] 缪小进, 夏思海, 武美萍, 等. 添加CeO₂对铝合金表面激光熔覆铝钛熔覆层性能的影响[J]. 金属热处理, 2021, 46(9): 234-240.
MIAO X J, XIA S H, WU M P, et al.Effect of Adding CeO₂ on Properties of Al-Ti Laser Clad Coating on Aluminum Alloy[J]. Heat Treatment of Metals, 2021, 46(9): 234-240.
[30] VISHNU V, PRABHU T R, VINEESH K P.Effect of Hard Anodizing and T6 Heat Treatment on the Dry Sliding Wear Behavior of AlSi₁₀Mg Fabricated by Direct Metal Laser Sintering[J]. Wear, 2025, 564: 205677.
[31] ZHOU Z Y, JIANG Z G, ZHENG Q Y, et al.Research on the Construction of Gradient Nanostructure and Anti- Tribocorrosion Behavior of Aluminum Alloy Surface[J]. Tribology International, 2024, 194: 109448.