[TheForge] Re: Rebound and Work

[Mike Spencer]

> How about this one--does a dead blow hammer do any good in forging? My 
> bet is no, you just make the shot in the head warmer...

I don't know what a dead blow hammer is but I infer that it's a hollow
steel hammer head almost but not quite filled with lead shot. (How'm I
doing? :-)

I'd agree.  Ignoring the fine details of the impact event, the fact
that there is rebound means that a force is exerted through a distance
on the hammer head -- presumably because the hammer-anvil-workpiece
combo acts as a spring or something similar -- thereby accerating the
hammer head in the up direction.

Using a shot-filled hammer wouldn't affect that mechanism so if the
shot-filled hammer fails to rebound where an ordinary one does, then
yes, I'd assume it was just heating the shot.

> Change in kinetic energy (scalar) is what counts and is what is
> converted to heat or smush.

Yeah.  And smush is eventually converted to heat, too, unless perhaps
under (weird?) circumstances where you actually cause some of the
inter-atomic bonds to end up in a higher energy state than before the
blow was struck.  Normally, you's expect the bonds to stay the same
(on average) or go to a lower state as in stress-relieving a cooled
weld by hammering.


- Mike

-- 
Michael Spencer                  Nova Scotia, Canada       .~. 
                                                           /V\ 
mspencer at tallships.ca                                     /( )\
http://home.tallships.ca/mspencer/                        ^^-^^

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