RE: [Fwd: Re: Furnace for Hall D] (fwd)

[Elton Smith <elton@jlab.org>]

---------- Forwarded message ----------
Date: Wed, 19 Jun 2002 12:38:49 +0100
From: James Kellie <J.Kellie@omega.Physics.Gla.Ac.Uk>
To: Jim Kellie <kellie@np.ph.gla.ac.uk>, 'Elliott Wolin' <wolin@jlab.org>
Cc: 'Elton Smith' <elton@jlab.org>, "'kross@jlab.org'" <kross@jlab.org>
Subject: RE: [Fwd: Re: Furnace for Hall D]

Dear Elliott,

Thankyou for trying to find a furnace which we could use to anneal our
diamonds.

I have just spoken to my contact at Drukker, and his advice is to try
temperatures between about 1100 cent to 1600 cent. Since diamond transforms
to carbon around 1800 cent, we clearly have to keep below that limit. The
other essential point is that if we heat the diamond in an atmosphere which
has any oxygen, it will burn like a small piece of coal !! I suggest we
start trying to anneal with some of the rejectwafers we have using a very
good vacuum- the thought of cremating a diamond wafer which could have a
value of $100,000 is one I would rather not contemplate. Apparently, it
would also be possible to heat the diamond in an atmosphere of
Argon/Hydrogen - called forming gas - or Nitrogen/Hydrogen. Do you know
anything about the availability of such gas mixtures?

If it turns out we can heat diamond to the desired temperature range, which
should be possible with the induction furnace if we place the diamond on a
suitable material since diamond has a very high thermal conductivity, then
we should try to assess the effect of the heating. The best way of doing
this would be to measure the rocking curve for the diamond.

I wonder if Brian knows to what temperature precision the 3000 cent furnace
can be set and also, if will work in vacuum, the vacuum which can be
achieved?

Regards,

Jim.

  

> ----------
> From: 	Elliott Wolin[SMTP:wolin@jlab.org]
> Sent: 	Tuesday, June 18, 2002 6:14 PM
> To: 	Jim Kellie
> Subject: 	[Fwd: Re: Furnace for Hall D]
> 
> <<File: wolin.vcf>>
> Hi Jim,
> 
> More oven questions...
> 
> 					Elliott
> 
> -------- Original Message --------
> Subject: Re: Furnace for Hall D
> Date: Tue, 18 Jun 2002 12:31:41 -0400
> From: "Brian J. Kross" <kross@jlab.org>
> Organization: Jefferson Lab
> To: Elliott Wolin <wolin@jlab.org>
> References: <3CED4AB7.66627A4C@jlab.org> <3CF6347F.32AAB33C@jlab.org>
> <3CF65B16.A8033359@jlab.org>
> 
> Elliot,
>     One more new oven, although maybe of questionable value.  Kevin Jordan
> just
> received a induction furnace that is allegedly good for 3,000.  It is an
> induction
> furnace.  Typically those work by inducing a field directly in your
> material so
> they
> won't work for diamonds.  His number is cell # 876-1742.  You might want
> to call
> him
> to see if it applicable.
> Brian
>