Corrosion resistance of plasma-anodized AZ91D magnesium alloy by electrochemical methods

被引：159

作者：

Barchiche, C. -E. ^{[1
]}

Rocca, E. ^{[1
]}

Juers, C. ^{[1
]}

Hazan, J. ^{[1
]}

Steinmetz, J. ^{[1
]}

机构：

[1] Univ Henri Poincare, Nancy Univ, CNRS 7555, Lab Chim Solide Mineral,UMR, F-54506 Vandoeuvre Les Nancy, France

来源：

ELECTROCHIMICA ACTA | 2007年 / 53卷 / 02期

关键词：

PEO; AZ91D magnesium alloy; anodic film; corrosion;

D O I：

10.1016/j.electacta.2007.04.030

中图分类号：

O646 [电化学、电解、磁化学];

学科分类号：

081704 ;

摘要：

Anodic coatings formed on magnesium alloys by plasma anodization process are mainly used as protective coatings against corrosion. The effects of KOH concentration, anodization time and current density on properties of anodic layers formed on AZ91D magnesium alloy were investigated to obtain coatings with improved corrosion behaviour. The coatings were characterized by scanning electron microscopy (SEM), electron dispersion X-ray spectroscopy (EDX), X-ray diffraction (XRD) and micro-Raman spectroscopy. The film is porous and cracked, mainly composed of magnesium oxide (MgO), but contains all the elements present in the electrolyte and alloy. The corrosion behaviour of anodized Mg alloy was examined by using stationary and dynamic electrochemical techniques in corrosive water. The best corrosion resistance measured by electrochemical methods is obtained in the more concentrated electrolyte 3 M KOH +0.5 M KF+0.25 M Na3PO4 center dot 12H(2)O, with a long anodization time and a low current density. A double electrochemical effects of the anodized layer on the magnesium corrosion is observed: a large inhibition of the cathodic process and a stabilization of a large passivation plateau. (c) 2007 Elsevier Ltd. All rights reserved.

引用

页码：417 / 425

页数：9

共 30 条

[21] Mechanisms underlying the formation of thick alumina coatings through the MAO coating technology [J].

Sundararajan, G ;

Krishna, LR .

SURFACE & COATINGS TECHNOLOGY, 2003, 167 (2-3) :269-277

[22] Structure and corrosion behavior of conversion coatings on magnesium alloys [J].

Umehara, H ;

Terauchi, S ;

Takaya, M .

MAGNESIUM ALLOYS 2000, 2000, 350-3 :273-282

[23]

Umehara H, 1999, ALUMINIUM, V75, P634

[24] CHARACTERIZATION OF PASSIVE LAYERS FORMED ON LEAD BY ELECTROCHEMICAL IMPEDANCE SPECTROSCOPY [J].

VARELA, FE ;

GASSA, LM ;

VILCHE, JR .

JOURNAL OF ELECTROANALYTICAL CHEMISTRY, 1993, 353 (1-2) :147-160

[25] Formation, structure and composition of anodic films on AM60 magnesium alloy obtained by DC plasma anodising [J].

Verdier, S ;

Boinet, M ;

Maximovitch, S ;

Dalard, F .

CORROSION SCIENCE, 2005, 47 (06) :1429-1444

[26] Characteristics of anodic coatings oxidized to different voltage on AZ91D Mg alloy by micro-arc oxidization technique [J].

Wang, Y ;

Wang, J ;

Zhang, J ;

Zhang, Z .

MATERIALS AND CORROSION-WERKSTOFFE UND KORROSION, 2005, 56 (02) :88-92

[27] Effects of spark discharge on the anodic coatings on magnesium alloy [J].

Wang, YH ;

Wang, J ;

Zhang, JB ;

Zhang, Z .

MATERIALS LETTERS, 2006, 60 (04) :474-478

[28] Phase formation in ceramic coatings during plasma electrolytic oxidation of aluminium alloys [J].

Yerokhin, AL ;

Lyubimov, VV ;

Ashitkov, RV .

CERAMICS INTERNATIONAL, 1998, 24 (01) :1-6

[29] Study on the environmentally friendly anodizing of AZ91D magnesium alloy [J].

Zhang, YJ ;

Yan, CW ;

Wang, FH ;

Lou, HY ;

Cao, CN .

SURFACE & COATINGS TECHNOLOGY, 2002, 161 (01) :36-43

[30] Development of anodic film on Mg alloy AZ91D [J].

Zhang, Yongjun ;

Yan, Chuanwei .

SURFACE & COATINGS TECHNOLOGY, 2006, 201 (06) :2381-2386

← 1 2 3 →