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From: smit~rols.com (Scott Mitchell)
Date: Tue, 15 Oct 1996 21:22:26 -0400 (EDT)
Subject: Re: Break-in & coaxing

Alright, you asked for it you got it...

>Date: 10/14/96 7:23 PM
>From: Larry D. Mitchell
> Ok, this is a topic that needs a lot of detail on the ype of
>materials that are used in the "Harps". The Alpha brasses are very
>susceptable to strain ageing/season cracking. These materials become so
>hardened and brittle from the ageing process that they crack in service
>without a load. On the other hand the B-12 Brasses have a low but
>non-zero suspectibility to percipitation harding following straining. So
>you have a wide range of responses to straining.
> The idea here is that strain induced dislocations are sites for
>the precipitation of solute atoms and/or nitrogen locks the dislocations
>preventing their easy mobility. Dislocation movement is the source of the
>plastic strain in a material. Tieing up these dislocations will result in
>a strengthened material. Thus, depending on the brass used this may or
>may not work.
> The best reference I can easily put my hand on is chapter 6 in
>"Mechanical Properties of Metal", by D. McLean, john Wiley & Sons, Inc.,
>NY,NY, 1962.
> It is clear that the particular material used in the construction
>is key as to whether the material will precipitation harden or strain age.
>Without more details one can't know.
>L. D. Mitchell, AKA DAD.

Aren't you sorry you asked.

Scott

__________________________________________________________________________
Scott Mitchell smit~rols.com

"As always, real research is best but speculation, wild-assed
guessing, and utter nonsense are inevitable." - Bo Bradham