On Fri, 26 Aug 2005 15:09:05 -0500, "s.morra"
wrote:

Ladies and Gentlemen, I want to ask you if you have experienced or know of
any stories about a particular phenomenon when quenching a red hot steel rod
in water. I have included repeated posting history below for reference.
One post is from Mr. Kolesnik in mid-2005, followed by my response to that
string when I discovered it. Then my two original posts follow that. If
you know about this phenomenon, please respond to the group here.

repeat Henry Kolesnik post on
I don't know if this is the right place to ask this question, but if it's
not please point me to the correct group.

Back in the fifties I recall heating the end of a 20 inch long piece of 1
inch cold rolled steel bar stock in a blacksmith forge to red hot. On
several occasions, instead of hammering the piece on an anvil I would plunge
it into the water because someone asked me to do something else. On these
occasions I noticed that the end that I was holding would seem to get much
hotter faster when plunged versus when hammering on the piece. For some
reason the heat traveled to the part I was holding faster when plunged
versus being forged. Is there a scientific reason for what happened or has
my memory deceived me?

(snip)

It's an illusion.

If you heat two bars identically, then plunge one in a quenching bath
while holding both, the rate of temperature increase at the ends
you're holding will initally be about the same.

Heat propagates thru a material at a rate determined by its thermal
conductivity, specific heat and temperature gradient. . This
process can be (has been) treated as a boundary value problem with
partial differential equations.

The illusion is caused by heat that is "on the way" from the heated
end to the held end. Quenching the hot end still leaves a hot region
in the middle, which will continue to propagate (now in both
directions) thru the bar. Quenching the end does not instantly
quench the middle, just as heating the end didn't instantly heat the
middle.