Dear Antonio,
as far as I know, austenite is just a solid solution
of a few mole-% of carbon in gamma-iron.
Thus, you essentially need the structure of gamma-Fe,
which is very simple, as it is an fcc metal
(space group Fm-3m, a = 3.6468 A, just one
Fe atom located on 0,0,0).
I found one ICSD entry for austenite.
However, the dissolved carbon is placed sharing
the Fe site in this structure, which I doubt makes
sense from the chemical point of view.
I would bet the carbon atoms are actually located
on interstitial sites instead.
Anyway, as we are talking about a few MOLE-%
of carbon here, and carbon is much lighter than
iron, I think neglecting the carbon will not
make much of a difference (both for the accuracy
of the calculated relative intensities and
the quantification in wt-%.
Thus, I would just use gamma-Fe as a replacement
for austenite here.
Cheers,
Frank
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Frank Girgsdies
Department of Inorganic Chemistry
Fritz Haber Institute (Max Planck Society)
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antonio josé wrote:
Dear All.
I trying analyze phases in a steel sample using X-Ray technique. The
analysis of X-Ray pattern shows that the main phases are ferrite and
austenite. The next step would be quantify these phases by Rietveld
method using TOPAS 3.0. I am looking for cif files for austenite and I
didn’t find it in WEB free database or in ICSD database.
Do anyone has this cif file or could tell me where I can find?
Thanks a lot,
Antonio José
[EMAIL PROTECTED]