A STUDY OF CORROSION INITIATION ON POLYIMIDE COATINGS

被引：68

作者：

BELLUCCI, F ^{[1
]}

NICODEMO, L ^{[1
]}

MONETTA, T ^{[1
]}

KLOPPERS, MJ ^{[1
]}

LATANISION, RM ^{[1
]}

机构：

[1] MIT,HH UHLIG CORROS LAB,CAMBRIDGE,MA 02139

来源：

CORROSION SCIENCE | 1992年 / 33卷 / 08期

关键词：

D O I：

10.1016/0010-938X(92)90131-L

中图分类号：

T [工业技术];

学科分类号：

08 ;

摘要：

The protective properties of thin polyimide (PI) films on aluminum and iron metallic substrates were studied using a.c. and d.c. electrochemical techniques. The effects of storage time, film thickness, and the synergistic effect of temperature (80-degrees-C) and relative humidity (85%) on the lifetime of the PI were investigated. The results obtained can be summarized as follows: (i) early failure was observed for the PI/Al samples tested directly after curing, while extended lifetime was observed for samples stored in a desiccator for 2 months before testing, (ii) early failure was also observed for the PI/Fe samples even after storage in a desiccator before testing, (iii) the lifetime increases by increasing the film thickness, and (iv) temperature and relative humidity (RH) dramatically affect failure. A mathematical model is presented to relate coating failure to salt uptake by the PI. By applying this model to the experimental findings, an estimate of the heterogeneities or defects in the PIs is given.

引用

页码：1203 / 1226

页数：24

共 42 条

[1] ELECTROLYTIC RESISTANCE IN EVALUATING PROTECTIVE MERIT OF COATINGS ON METALS [J].