On Fri, 9 Oct 2015 04:33:45 -0700 (PDT), "
wrote:

On Friday, October 9, 2015 at 6:44:38 AM UTC-4, Lloyd E. Sponenburgh wrote:
" fired this volley in
:

My guess is that it is one of the structural steels and the fact that
it does not rust is because it is hot dipped galvanized.

Don... freshly-cut ends and ground areas do not rust, either! That was in
the original post...

L

So if the fresh cut ends do not rust, why did they bother to galvanize it?

Dan

I'm interested to see what Lloyd's analysts say, but a couple of
points: First, galvanizing prevents rust not, primarily, by forming a
barrier, but by creating a galvanic cell with the ferrous metal, and
the galvanic protection can extend for 1/8" or more into cut areas.
You can really see this on marine hardware that's been nicked up. Even
exposed to salt water, those bare spots and edges of steel don't rust
much.

Second, your point is the one that prompted me to write that
(unwelcome) post to Lloyd. They don't galvanize rust-resistant alloys.

I'm betting that it's some plain-carbon alloy -- either a clean piece
of mild steel, as Iggy suggested, or, much more likely just based on
what simple structural shapes are usually made of, some loosely
specified structural alloy (A36, etc.). It could also be Chinese or
American re-melt junque -- one of the non-grades of scrap re-melt,
like the railroad rails used for bedframe steel, or the dregs used to
make coat hangers.

Most structural steel is pretty much crap, to a machinist or a
fabricator.

--
Ed Huntress