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ekjustice t1_isge6q2 wrote

Reply to comment by [deleted] in How come some Galvanized steel panel have patterns? by LameTrouT

It has a current going through the liquid and into the metal object, that's why they call it "galvanized". The electricity bonds the zinc to the steel better than just dipping it.

Some items are just dipped in liquid zinc "hot dipped". This leaves more zinc on the item and tends to be more expensive.

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the_snook t1_isghskh wrote

It can also depend on the type of coating. Some "galvanized" steel is actually Zincalume, which is coated with a zinc-aluminium-silicon alloy. From memory, I think Zincalume has more prominent crystal structure (though maybe it was just because of the particular manufacturer of the stuff I saw).

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JenJudy t1_ishjwho wrote

The term galvanized originally meant electroplated, and didn't specify what metal was used, but it gradually came to mean primarily electroplating with zinc. In modern usage, it simply means coated with zinc, regardless of whether it's electroplated or hot dipped, at least according to Merriam-Webster who give this definition:

>: to coat (iron or steel) with zinc

>especially : to immerse in molten zinc to produce a coating of zinc-iron alloy

This is consistent with the way the term is used indescribing finishes on bolts, etc, by both professional sources such as McMaster or consumer sources such as home depot. The most common options are called zinc plated, which is electroplated, and hot dip galvanized, which does not involve an electric chemical process, in contrast to the origin of the term.

It's surely irritating to electrochemists that the meaning has shifted to go beyond electrochemical processes, but language change is inevitable.

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