Formation and characterisation of Ti-Zr based conversion layers on AA6060 aluminium

被引:144
作者
Lunder, O
Simensen, C
Yu, Y
Nisancioglu, K
机构
[1] SINTEF Mat Technol, N-7465 Trondheim, Norway
[2] Norwegian Univ Sci & Technol, N-7491 Trondheim, Norway
关键词
chemical conversion; aluminium;
D O I
10.1016/j.surfcoat.2003.11.003
中图分类号
TB3 [工程材料学];
学科分类号
0805 ; 080502 ;
摘要
Formation of a Ti-Zr based conversion layer on AA6060 aluminium has been studied electrochemically and by use of various surface analytical methods. Measurements show that the alpha-Al(Fe,Mn)Si particles present in AA6060 are cathodic to the aluminium matrix in a fluorotitanate-zirconate (H2TiF6-H2ZrF6) based solution, and reduction reactions occur predominantly on the particles. The alkaline diffusion layer thus formed causes preferential deposition of a hydrated Ti and Zr oxide covering the particles and surrounding areas, eventually leading to a conversion layer with significant variations in thickness. In addition to substrate metallurgy, agitation and pH of the conversion bath are factors that significantly control the conversion layer deposition. The conversion layers formed cause only a small reduction in the cathodic activity of the alpha-Al(Fe,Mn)Si particles and do not impart improved corrosion resistance of the AA6060 alloy in chloride solution. (C) 2003 Elsevier B.V. All rights reserved.
引用
收藏
页码:278 / 290
页数:13
相关论文
共 17 条
[1]  
[Anonymous], ALUM T
[2]   THE MORPHOLOGY, STRUCTURE AND MECHANISM OF GROWTH OF CHEMICAL CONVERSION COATINGS ON ALUMINUM [J].
BROWN, GM ;
SHIMIZU, K ;
KOBAYASHI, K ;
THOMPSON, GE ;
WOOD, GC .
CORROSION SCIENCE, 1992, 33 (09) :1371-1385
[3]   Investigation of fluoacid based conversion coatings on aluminum [J].
Deck, PD ;
Moon, M ;
Sujdak, RJ .
PROGRESS IN ORGANIC COATINGS, 1998, 34 (1-4) :39-48
[4]  
DECK PD, 1992, MET FINISH, V90, P29
[5]   Corrosion behaviour of fluotitanate pretreated and painted aluminium sheets [J].
Fedrizzi, L ;
Deflorian, F ;
Bonora, PL .
ELECTROCHIMICA ACTA, 1997, 42 (06) :969-978
[6]  
HOLLINGSWORTH EH, 1987, ASM HDB CORROSION, V13
[7]  
Hughes AE, 1996, MATER SCI TECH SER, V12, P928, DOI 10.1179/026708396790122071
[8]  
HUGHES AE, 1996, INTERFINISH 96 WORLD
[9]  
Leth-Olsen, 1996, THESIS NORWEGIAN U S
[10]  
LUNDER O, 1993, PROGR UNDERSTANDING, V1, P1249