In general, "exudation" is a phenomenon described for AZS in superstructure, while "corrosion" is almost always referred to glass contact blocks.

This is a simplification that, some time, is not enough to describe real situations observed in industrial applications. In fact, though exudation is the prevalent visible occurrence in superstructure and corrosion is the prevalent visible occurrence in glass contact, it must be made clear that corrosion is sometime non neglectable in superstructure, while exudation in glass contact is the main cause of impaired performance of AZS f.c. under particular working conditions.

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