Phosphate coatings porosity: Review of new approaches

被引:7
作者
Kwiatkowski, L [1 ]
机构
[1] Inst Precis Mech, Warsaw, Poland
关键词
phosphate coatings; porosity; evaluation; electrochemical methods; voltammetric methods; corrosion current; electrochemical impedance spectroscopy; polarisation resistance; electrochemical noise analysis; noise resistance; scanning kelvin probe; volta potential; pretreatment; post-treatment; corrosion resistance;
D O I
10.1179/026708404225016526
中图分类号
TB3 [工程材料学];
学科分类号
0805 ; 080502 ;
摘要
The value of a phosphate coating's porosity varies between 0.1 and 25%, depending on process details and the method of determination. In the case of electrochemical methods, low amplitude or other low invasive techniques are recommended. The assumption that the mechanism of electrochemical/chemical reaction in pores of the phosphate coating and bare metal is the same is. often not verified. The free surface at the bottom of the pores was found to be modified in pretreatment and post-treatment operations and in some cases was found to be more active than the clean bare metal surface. The reference sample should be at least treated in diluted phosphoric acid that has the same free and total acidity as the phosphating bath.
引用
收藏
页码:292 / 298
页数:7
相关论文
共 12 条
[1]   Interpretation of electrochemical noise data [J].
Cottis, RA .
CORROSION, 2001, 57 (03) :265-285
[2]  
KAYSSER F, 1972, GALVANOTECHNIK, V6, P11
[3]   THE MECHANISM FOR THE CATHODIC DELAMINATION OF ORGANIC COATINGS FROM A METAL-SURFACE [J].
LEIDHEISER, H ;
WANG, W ;
IGETOFT, L .
PROGRESS IN ORGANIC COATINGS, 1983, 11 (01) :19-40
[4]   A simple testing method for quality control of phosphate coatings based on impedance measurements [J].
Lendvay-Gyorik, G ;
Mészáros, G ;
Lengyel, B .
JOURNAL OF APPLIED ELECTROCHEMISTRY, 2002, 32 (08) :891-896
[5]   IMPEDANCE SPECTROSCOPY AND OTHER ELECTROCHEMICAL IN-SITU INVESTIGATIONS OF THE PHOSPHATING PROCESS [J].
LOSCH, A ;
SCHULTZE, JW .
JOURNAL OF ELECTROANALYTICAL CHEMISTRY, 1993, 359 (1-2) :39-61
[6]  
MANSFELD F, 2000, P NAC ANN C CORR 200
[7]  
MCDONALD D, 1987, IMPEDANCE SPECTROSCO, P301
[8]   STUDY OF THE COVERAGE OF PHOSPHATED STEEL SURFACES BY IMPEDANCE METHOD [J].
MESZAROS, L ;
LENDVAYGYORIK, G ;
LENGYEL, B .
MATERIALS CHEMISTRY AND PHYSICS, 1989, 23 (03) :267-286
[9]  
PONTE HJ, 2002, MAT RES, V5, P339
[10]  
RAUSCH W, 1990, PHOSPHATIERUNG METAL, P289