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Materie unter extremen Bedingungen Poster: Do., 13:00–15:30 D-P366
MAX200x: XRD under High Pressure and High Temperature Conditions
Frank Schilling 1 , Christian Lathe 1,2 , Hans-Joachim Müller 2 , Hans-Josef
Reichmann 2
1 GFZ Potsdam, Telegrafenberg, 14473 Potsdam, Germany. – 2 DESY-HASYLAB,
Notkestr. 85, 22603 Hamburg, Germany.
Fig. 1: MAX200x surrounded from
aluminium-lead-aluminium hutch at
DESY-HASYLAB.
In-situ X-ray diffraction experiments under ex-
treme pressure p and temperature T conditions
at synchrotron beam lines become more and more
important for Geosciences, Material Sciences,
Chemistry and Physics. Especially for Geoscientists
mineral reactions, phase transitions, as
wheel as fluid rock interaction at enhanced p and
T seem to have the potential to strongly influence
and control the dynamic motions within the
upper and lower mantle of the Earth. Around
25 GPa and 2000 K are required to simulate these
processes in the laboratory. The new installed
MAX200x (Fig. 1) is an excellent tool for these
ambitious experiments. The MAX200x is operated
in the double-stage compression mode, in
which the first stage is the DIA-type apparatus
with six anvils and the second stage consists of
eight anvils. One corner each of all eight cubes
is truncated orthogonally to the spatial diagonal.
The octahedral sample is compressed by
the truncated corner of eight inner cubic anvils, which, in turn, is compressed by the
outer first stage six anvils. Either tungsten carbide or cubic boron nitride is used for
the second stage anvils. This system has a capability of generating pressures up to
25 GPa and temperatures exceeding 2000 K by a resistance furnace. The MAX200x
is movable in y- and z-direction for ± 125 mm and can be rotated up to ± 15. For
detecting the X-rays we use a high purity Germanium detector which is cooled by an
electrical cooler. The Ge-detector is mounted on a goniometer which is adjusted to the
centre of the press and can rotate from 0 ◦ up to 15 ◦ . It is assembled on a stepper motor
driven table which can be displaced in z-, x-, and y-direction. For deformation experiments
and viscosity studies under in situ conditions X-radiography is indispensable.
Furthermore, to measure X-ray absorption as a tool for e.g. in situ density measurements
of melts an ionization chamber is available [1]. First experimental results will
be presented.
[1] C. Lathe, F. Schilling, H.J. Müller, H.J. Reichmann and J. Lauterjung, HASYLAB
Annual Report (2005).