An organic chromium-free conversion coating on AZ91D magnesium alloy

被引：125

作者：

Chen, Xiaoming ^{[1
]}

Li, Guangyu ^{[1
]}

Lian, Jianshe ^{[1
]}

Jiang, Qing ^{[1
]}

机构：

[1] Jilin Univ, Coll Mat Sci & Engn, Minist Educ, Key Lab Automobile Mat, Changchun 130025, Peoples R China

来源：

APPLIED SURFACE SCIENCE | 2008年 / 255卷 / 05期

关键词：

Chromium-free conversion coating; Tannic acid; Corrosion; XPS; IR;

D O I：

10.1016/j.apsusc.2008.07.092

中图分类号：

O64 [物理化学（理论化学）、化学物理学];

学科分类号：

070304 [物理化学]; 081704 [应用化学];

摘要：

Traditional conversion coatings on magnesium alloys are usually immersed in a solution containing hexavalent chromium compounds. However, the replacement treatments have been proposed by the present environmental driving to eliminate hexavalent chromium. In this work, a tannic acid based conversion coating on AZ91D magnesium alloy was obtained by treatment in a solution containing tannic acid and ammonium metavanadate. SEM, XPS and IR were used to determine the morphology and structure of the conversion coatings. Continuous and uniform conversion coating was deposited on AZ91D alloy and the main components of the coatings were Al2O3, MgF2 and penta-hydroxy benzamide magnesium complex. The formation mechanism of the coating was discussed. Polarization measurement and salt spray test showed that the corrosion resistance of the conversion coating was much higher than that of traditional chromate conversion coating. (C) 2008 Elsevier B. V. All rights reserved.

引用

页码：2322 / 2328

页数：7

共 25 条

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The corrosion behavior of scandium alloyed Al 5052 in neutral sodium chloride solution [J].