Chromating is a process in electroplating that acts as an independent protection against corrosion and as a primer for metals. It is an electroless, chemical surface treatment with solutions made of chromium salts. Chromate coatings provide low electrical contact resistance. and are usually more favourable than the electrical resistance of untreated parts.
Chemical layers of aluminium form inorganic layers or conversion layers, which consist mostly of oxide hydrates.
These conversion layers are only 1-2 µm thick. Chromated aluminium components are therefore very suitable for aluminium housing parts that must be conductive to one another to ensure the shielding effect of the housing. Insulating anodised layers behave unfavourably here.
Thicker yellow chromate layers achieve a higher level of corrosion protection than thin, clear layers.
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