La dégradation des métaux protégés par peinture

Méthodes et moyens d’étude Première partie

Study methods of the corrosion resistance of metals protected by paints

Laboratoire de Physique du Solide, Institut de Physique Université de Constantine (Algérie)

Abstract

The protection of metallic materials constitute a wide field of investigation, where manufacturer and user of paints as well as searcher must act in concert. We present here the usual tests used to caracterise organic films quality and corrosion resistance of underlying metal.

Study methods can be divided into three groups: mecanic tests and non-electrochemical corrosion tests, relatively quick, usually used by manufacturer and industrial user, and electrochemical tests.

These latter, are preferentially used to evaluate films performance and behaviour in relation with metal corrosion. However, often, these methods can’t allow to predict accurately the behaviour of metal/organic films systems, and important efforts have been done on the reliability of the electrochemical measures to find correlation with natural ageing. Indeed, these measures must find their significations in the natural degradation of organic films on one hand, and in the interface reactivity on the other hand, taking in consideration the synergycal phenomena which appeared.

So, in spite of considerable works realised in this fiefd, exposition tests in real times and sites remained incomparably more sure when the question is to select paints systems for special application.