Katanax X-FLUXER, Manual

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Heating above those temperatures could cause flux evaporation that could bias
the subsequent analysis.
A warning will appear when going over 1100°C. Please contact Katanax if you
feel that your sample type needs higher temperatures, so that we can assist and
develop a lower-temperature method.
Duration
Step duration (mm : ss) is also adjusted by
pressing on the plus and minus buttons. The
actual step timer will start once the furnace
has reached the temperature set for this step. Hence, the length of a step is
actually the sum of the time required by the furnace to increase up to the step
temperature, plus the duration parameter. For each step, the duration parameter
is limited to 19 minutes and 55 seconds, except if ramping is in use (see below).
Ramping
The ramping parameter determines how fast
the furnace will increase its temperature to
reach the one set in the current step. In most
application, we want the furnace to heat up as
fast as possible, but it is also possible to set this parameter (by pressing on the
plus and minus buttons) to limit the heat-up rate. The other ramping values
(besides Fast) are given in °C/minute.
Slow heat-up rates are particularly useful with a solid oxidizer, when we want it to
react slowly over a temperature range, of typically about 100°C.
Crucible rocking speed and amplitude
The crucible content is mixed by a back-and-
forth rocking motion, whose amplitude (in
degrees) and speed (in % of the max) can be
controlled by means of the plus and minus
buttons.
Typically, initial heating steps call for very
little rocking. This allows for the oxidizer to react, and for flux to melt without
risking overflowing from the crucible (molten flux takes up less volume than
powder flux).
When the flux is completely dissolved and pouring approaches, speed and
amplitude can be used more generously. One exception would be with samples
containing gases. Those samples produce bubbles that can remain trapped in the
melt, and de-gassing the melt is sometimes better achieved with very slow
speeds and large amplitudes, before pouring.
Pouring step
The pouring step occurs when the crucible is tilted forward quickly, to empty its
contents either into a mold or a beaker containing acid. However, pouring can be
turned off altogether, for those fusion types where pouring is not desired: fusions
in sodium peroxide or potassium pyrosulfate.