I checked out he site below and I must say, as the man on TV says, "I, I am
a skeptic". Unfortunately they do not define the metallurgical process
involved in the stress reduction. They make note of "subharmonic"
frequencies however that is a really really general term. Sub harmonics
would be less than the fundamental frequency and for a structure like the
one being welded on can be quite low. We had frequencies below 1 hz for the
first fundamental on some of the space station hardware. Oh, by the way, we
put the ENTIRE habital volume and Node volume in a shaker table, suspended
it like it would be in the shuttle and shook the snot out of it. Didn't
anybody I know every say we were sress relieving it. And if we were, NASA
would have been right there with their backs ready for a pat on it for doing
it. As a matter of thought, I would think that any vibration would be in the
nature of strain hardening rather than relieving (due to metal flex, however
microscopically). If I had the choice, and I don't, I would like to have my
parts aged at the expected operating temperaure before any final machining.
Mother nature can relieve stress over time or at least it comes into balance
with itself.
Nice thread, this.
mayf
----- Original Message -----
From: "Steve Christophersen" <sotacd@ameritech.net>
To: "Albaugh, Neil" <albaugh_neil@ti.com>; "'Russel Mack'"
<rtmack@concentric.net>; "'Doug Odom'" <popms@thegrid.net>; "Bryan Savage"
<basavage@earthlink.net>
Cc: "Bob Jepson" <Bobbyhotrods@attbi.com>; "Land Speed"
<land-speed@autox.team.net>
Sent: Monday, December 16, 2002 3:04 PM
Subject: Re: Stress relief
> Check out: www.bonal.com/meta-lax/
>
>
> Subject: RE: Stress relief
>
>
> > Russ;
> >
> > I thought about that possibility but it seems like it (the Rodek block)
> > would have more vibration-induced stresses when it was a running engine
> than
> > they could ever generate with a shake table. I wonder if they have any
> data
> > showing its benefit?
> >
> > Regards, Neil Tucson, AZ
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/// what is needed. It isn't that difficult, folks.
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