研究了一种新的AZ31B镁合金交流电微弧氧化(MAO)工艺,采用了对环境更加友好的含硅酸盐的稀碱溶液作为电解质.结果发现氧化过程分为2个阶段,膜厚与微弧氧化时间呈抛物线关系.形貌观察表明,微弧氧化膜由一个致密层和一个多孔层组成.致密层的厚度约占整个膜厚的40％,膜表面的20％均匀分布着直径1 ～3 μm的孔.动电位极化测量显示,该新型微弧氧化膜的耐蚀性有明显提高,腐蚀电流降低了2个数量级,而自腐蚀电位正移了0.07 V.盐雾试验结果同样证实微弧氧化膜的耐蚀性有大幅度提高.
A new micro-arc oxidation (MAO) process for AZ31B magnesium alloy,based on a more environmentally friendly electrolyte solution consisting of diluted alkaline solution with silicate under alternating current, was investigated.The findings show that oxidation behavior can be divided into two stages.The relation between film thickness and anodizing time is of parabolic dependence.The morphological views indicate that the film consists of a compact layer and a porous layer.The compact layer thickness is approximately 40％,and the 1-3 μm pores are evenly distributed with a coverage of about 20％ of the film.It is shown that new coating displays obvious improvement in the corrosion resistance by potentiodynamic polarization tests.The corrosion current is reduced by two orders of magnitude,and free corrosion potential shifts positively by 0.07 V.The results for salt spray testing also indicate that the corrosion resistance of MAO are promoted largely.
参考文献
| [1] | Z.Yaug,J.P.Li,J.X.Zhang,G.W.Lorimer,J.Robson.REVIEW ON RESEARCH AND DEVELOPMENT OF MAGNESIUM ALLOYS[J].金属学报(英文版),2008(05):313-328. |
| [2] | J. Choi;S. Nakao;J. Kim .Corrosion protection of DLC coatings on magnesium alloy[J].Diamond and Related Materials,2007(4/7):1361-1364. |
| [3] | YABUKI A;SAKAI M .Anodic films formed on magnesium in organic,silicate-containing electrolytes[J].Corrosion Science,2009,51(04):793-798. |
| [4] | Ghasemi A;Raja VS;Blawert C;Dietzel W;Kainer KU .Study of the structure and corrosion behavior of PEO coatings on AM50 maginesium. alloy by electrochemical impedance spectroscopy[J].Surface & Coatings Technology,2008(15):3513-3518. |
| [5] | 孙德新,孙大千,李金宝,李明高,殷世强.镁合金焊接技术的研究进展及应用[J].材料导报,2006(08):122-126. |
| [6] | REINERS G;GRIEPENTROG M .Hard coatings on magnesium alloys by sputter deposition using a pulsed d.c.bias voltage[J].Surface and Coatings Technology,1995,76/77:809-814. |
| [7] | Helene Ardelean;Isabelle Frateur;Philippe Marcus .Corrosion protection of magnesium alloys by cerium, zirconium and niobium-based conversion coatings[J].Corrosion Science: The Journal on Environmental Degradation of Materials and its Control,2008(7):1907-1918. |
| [8] | Wei Shang;Baizhen Chen;Xichang Shi .Electrochemical corrosion behavior of composite MAO/sol-gel coatings on magnesium alloy AZ91D using combined micro-arc oxidation and sol-gel technique[J].Journal of Alloys and Compounds: An Interdisciplinary Journal of Materials Science and Solid-state Chemistry and Physics,2009(1/2):541-545. |
| [9] | Liyuan Chai;Xia Yu;Zhihui Yang;Yunyan Wang;Masazumi Okido .Anodizing Of Magnesium Alloy Az31 In Alkaline Solutions With Silicate Under Continuous Sparking[J].Corrosion Science: The Journal on Environmental Degradation of Materials and its Control,2008(12):3274-3279. |
| [10] | LUO Sheng-lian,DAI Lei,ZHOU Hai-hui,CHAI Li-yuan,KUANG Ya-fei.New anodizing process for magnesium alloys[J].中南工业大学学报（英文版）,2006(02):141-145. |
| [11] | KURZE P.Corrosion and Corrosion Protection of Magnesium[A].Weinheim:WileyVCH Verlag GmbH & Co.KGaA,2003 |
| [12] | Guo HF;An MZ .Growth of ceramic coatings on AZ91D magnesium alloys by micro-arc oxidation in aluminate-fluoride solutions and evaluation of corrosion resistance[J].Applied Surface Science: A Journal Devoted to the Properties of Interfaces in Relation to the Synthesis and Behaviour of Materials,2005(1/3):229-238. |
| [13] | Formation of micro-arc oxidation coatings on AZ91HP magnesium alloys[J].Corrosion Science: The Journal on Environmental Degradation of Materials and its Control,2009(12):2820. |
| [14] | Arrabal, R;Matykina, E;Hashimoto, T;Skeldon, P;Thompson, GE .Characterization of AC PEO coatings on magnesium alloys[J].Surface & Coatings Technology,2009(16):2207-2220. |
| [15] | Xin SG;Song LX;Zhao RG;Hu XF .Influence of cathodic current on composition, structure and properties of Al2O3 coatings on aluminum alloy prepared by micro-arc oxidation process[J].Thin Solid Films: An International Journal on the Science and Technology of Thin and Thick Films,2006(1):326-332. |
| [16] | 王燕华,王佳,张际标.电流密度对AZ91D镁合金微弧氧化膜性能的影响[J].中国腐蚀与防护学报,2005(06):332-335. |
| [17] | Blawert, C;Heitmann, V;Dietzel, W;Nykyforchyn, HM;Klapkiv, MD .Influence of process parameters on the corrosion properties of electrolytic conversion plasma coated magnesium alloys[J].Surface & Coatings Technology,2005(1/4):68-72. |
| [18] | R. Arrabal;E. Matykina;F. Viejo;P. Skeleton;G.E. Thompson .Corrosion resistance of WE43 and AZ91D magnesium alloys with phosphate PEO coatings[J].Corrosion Science: The Journal on Environmental Degradation of Materials and its Control,2008(6):1744-1752. |
| [19] | FONTANA M G.Corrosion Engineering[M].New York:mcgraw-hill Book Company,inc,1986:196-197. |
- 下载量()
- 访问量()
- 您的评分：
-
10%
-
20%
-
30%
-
40%
-
50%