Paint coatings continued weathering

Natural weathering such as wind and rain erosion can eventually lead to failure of protective coatings of composites including paints, and the underlying fiber -resin material, if left exposed, is then vulnerable to continued weathering [29]. Water penetration and UV radiation are other factors damaging composites. 

Specification for electroplated coatings of 65/35 tin/nickel alloy Method for the evaluation of results of accelerated corrosion tests on metallic coatings Methods of test for paints Cross-cut test Pull-off test for adhesion Resistance to artificial weathering (enclosed carbon arc) and Addendum No. 1 Resistance to continuous salt spray Notes for guidance on the conduct of natural weathering test... 

In all the paint systems tested in the atmosphere, the presence of the chloride contaminant at its highest concentration, causes the appearance of small blisters. Such blisters may in time burst due to the oxide built-up inside them, as was seen in the case in the CR system ("Table III.") In the P system ("Table III."), the blistering seen with the third level of chlorides continues after two years outdoor exposure, without rust coming through the coating. This same effect is also seen in salt fog test panels, but it does not appear in those test specimens subjected to accelerated weathering tests. 

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