Corrosion protection of aluminum metal-matrix composites

被引:39
作者
Greene, HJ [1 ]
Mansfeld, F [1 ]
机构
[1] UNIV SO CALIF,DEPT MAT SCI,CORROS & ENVIRONM EFFECTS LAB,LOS ANGELES,CA 90089
关键词
Al; 6061; A356; 2009; 2014; aerospace applications; aluminum; anodization; current density; electrochemical impedance spectroscopy; metal-matrix composite; pitting potential; potentiodynamic polarization;
D O I
10.5006/1.3290276
中图分类号
T [工业技术];
学科分类号
08 ;
摘要
Corrosion protection of aluminum metal-matrix composites (MMC) by anodizing treatments was investigated, Electrochemical behavior of MMC without protection also was investigated. Electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization measurements were used to characterize the properties of protective surface layers. Materials studied were Al 6061/SiC (UNS A96061), alloy A356/SiC (UNS A13560), Al 2009/SiC (UNS A92009), Al 2014/Al2O3 (UNS A92014) and Al 6061/Al2O3 with various reinforcement concentrations, The MMC had similar corrosion (E-corr) and pitting (E-pit) potentials as the matrix alloy, The cathodic current density for oxygen reduction in 0.5% N sodium chloride (NaCl) increased for Al 6061/SiC MMC with reinforcement concentration, which was attributed to electrochemically active interfaces between the matrix and the reinforcement particles. Anodizing and hot-water sealing were less effective for MMC than for the matrix aluminum alloys, The reinforcement particles produced a more porous structure of the anodized layer for MMC. improved results were noted for dichromate sealing, where chromium (Cr6+) in the pores of the outer oxide acted as an inhibitor, The effectiveness of corrosion protection methods decreased with increasing reinforcement concentration and was a function of the matrix alloy bur not of the reinforcement material, The observed reduction in corrosion protection was believed to result from corrosion-susceptible interfaces formed between the reinforcement particles and the matrix.
引用
收藏
页码:920 / 927
页数:8
相关论文
共 21 条
[1]   Corrosion protection of an Al 6092/SiCp metal matrix composite [J].
Chen, C ;
Mansfeld, F .
CORROSION SCIENCE, 1997, 39 (06) :1075-1082
[2]  
De Levie R., 1967, ADV ELECTROCH EL ENG
[3]  
DIGNARDBAILEY LM, 1989, ADV STRUCTURAL MAT
[4]  
GREENE H, 1992, COMPOSITION THESIS U
[5]  
KAESCHE H, 1985, METALLIC CORROSION
[6]   CORROSION PROTECTION OF AL/SIC METAL MATRIX COMPOSITES BY ANODIZING [J].
LIN, S ;
GREENE, H ;
SHIH, H ;
MANSFELD, F .
CORROSION, 1992, 48 (01) :61-67
[7]  
Lucas K.A., 1993, CORROSION ALUMINUM B
[8]   SURFACE MODIFICATION OF AL-ALLOYS AND A1-BASED METAL MATRIX COMPOSITES BY CHEMICAL PASSIVATION [J].
MANSFELD, F ;
LIN, S ;
KIM, S ;
SHIH, H .
ELECTROCHIMICA ACTA, 1989, 34 (08) :1123-1132
[9]  
Mansfeld F., 1994, British Corrosion Journal, V29, P194
[10]   PITTING AND PASSIVATION OF AL-ALLOYS AND AL-BASED METAL MATRIX COMPOSITES [J].
MANSFELD, F ;
LIN, S ;
KIM, S ;
SHIH, H .
JOURNAL OF THE ELECTROCHEMICAL SOCIETY, 1990, 137 (01) :78-82