The effect of vibratory mill induced mechanical activation on the change of
the particle size, crystallinity and the phase transformations of the
minerals present in the activated material, was studied with the purpose of
decreasing of the sintering temperature of talc (Mg3Si4O10(OH)2) as raw
material which is the basic component of the steatite ceramics. The aims of
the conducted investigation were, also, increasing of the reactivity of the
comminuted raw material and establishing of the optimal activation period.
The properties of the activated talc induced by mechanical force were
expressed in form of the grain inertia change which was measured by means of
automatic grain counter. Mechanically activated grains are the most
convenient mineral form for physical concentration since the energy change of
the mill-material system is recorded on them. The effect of dry grinding on
the structure, particle size and shape of talc was studied by means of XRD,
DTA and SEM/EDS methods. Activation of talc produced an increase of the
starting surface area value progressively from 4.5 m2/g up to a maximum of
108.5 m2/g achieved at 30 min. A subsequent decrease of rate of surface area
change and the rate of size reduction were observed following the prolonged
grinding. Talc activated in vibratory mill for optimal 30 min showed
properties which positively influence the decrease of sintering temperature
and the increase of the sintering rate of steatite ceramics.
Mechanical activation as sintering pre-treatment of talc for steatite ceramics
