View Single Post
  #3   Report Post  
Ed Huntress
 
Posts: n/a
Default Old Steel - New Steel

"Grant Erwin" wrote in message
...
Most steel made in this country now comes from melted-down cars, not
from mined iron ore. Such steel meets minimum specifications but you
may find anomalies like local hard spots (where a chromed ball bearing
was melted in for example). Many so-called "mild steels" today will
harden somewhat if heated and quenched strongly.

Maybe that's what he was talking about. - GWE


It depends on what you buy, Grant. If you buy AISI graded steel, it's
somewhat better today than it's ever been -- if it's made in the US, Europe,
or Japan (probably Australia, too, but I don't know how careful they are
with their grading of carbon steels).

The remelted scrap is used mostly in construction and other applications
that don't demand strict adherence to alloys, only to certain properties of
strength and elongation.

If you buy the junk in hardware stores, you may be getting anything.

Note the Jim's authority on old steel is a welder. He may have gotten stung
by some "mild" steel that was actually a construction grade. The weldability
of that stuff varies quite a bit.

Ed Huntress