AN IMPEDANCE SPECTROSCOPY STUDY OF THE DEGRADATION MECHANISM FOR A MODEL EPOXY COATING ON MILD-STEEL

被引:73
作者
GEENEN, FM [1 ]
DEWIT, JHW [1 ]
VANWESTING, EPM [1 ]
机构
[1] TNO,CTR POLYMER MAT,DEPT PAINT,2600 AB DELFT,NETHERLANDS
关键词
D O I
10.1016/0033-0655(90)80007-L
中图分类号
O69 [应用化学];
学科分类号
081704 ;
摘要
The degradation mechanism of an unmodified model epoxy coating on a steel substrate has been studied by the introduction of an artificial hole into the coating and subsequently measuring the electrical impedance of the system as a function of time of exposure to a 3% NaCl solution. A new procedure was used to determine a 'most probable equivalent circuit' from the impedance data. From changes in the value of the components of this equivalent circuit with exposure time, detailed information was obtained on physical phenomena occurring during the degradation of the defective coatings. A first step in the verification of the physical meaning of the components was made by varying the type and size of the defect and the aeration of the electrolyte, and by comparing the changes of the components with changes in the corrosion potential. A newly developed artificial defect type with special characteristics was used. © 1990.
引用
收藏
页码:299 / 312
页数:14
相关论文
共 14 条
  • [1] ASARI M, 1987, CORROS ENG, V36, P129
  • [2] BOUKAMP B, 1989, 9TH P EUR C CORR UTR
  • [3] DINGS MMM, 1989, 20TH P FATIPEC C NIC
  • [4] FELIU S, 1984, PITTURE VERNICI, V7, P17
  • [5] BLISTERING OF PAINT FILMS AND FILIFORM CORROSION
    FUNKE, W
    [J]. PROGRESS IN ORGANIC COATINGS, 1981, 9 (01) : 29 - 46
  • [6] GEENEN FM, 1988, INTERNAL PROJECT COM
  • [7] GEENEN FM, 1989, 9TH P EUR C CORR UTR
  • [8] GOWERS KR, 1986, MATERIALS SCI FORUM, V8, P289
  • [9] INTERPRETATION OF LOW-FREQUENCY AC IMPEDANCE DATA FOR ORGANIC COATINGS ON MILD-STEEL
    HEPBURN, BJ
    GOWERS, KR
    SCANTLEBURY, JD
    [J]. BRITISH CORROSION JOURNAL, 1986, 21 (02): : 105 - 108
  • [10] MACDONALD DD, 1989, P NATO ADV STUDY I