Influence of mechanical activation on elelctrical properties of cordierite ceramics

Abstract

Cilj ovog istraživanja je bio da ispita moguće korelacije funkcionalnih svojstava kordijeritne keramike u funkciji od pripreme polazne smeše. Trokomponentni sistem sastava MgO+Al2O3+SiO2 u odnosu 2:2:5 je pripremljen sa dodatkom 10% Bi2O3. Smeša je mehanohemijski aktivirana 5 i 240 minuta u mlinu sa keramičkim kuglama i sinterovana u temperaturnom opsegu od 1173-1573K. Strukturne transformacije su praćene rendgenostrukturnom analizom. Kvantitativne promene funkcionalnih svojstava uzoraka praćene su merenjem kapacitivnosti Cc, električne otpornosti Rρ, i tangensa ugla dielektričnih gubitaka. Rezultati su dokazali korelaciju između mehanohemijske aktivacije i svojstava kordijeritne keramike.

The goal of the presented research was to find a possible correlation of the process parameters and functional properties of cordierite based ceramic materials. A three component oxide mixture was prepared containing MgO+Al2O3+SiO2 in the 2:2:5 ratio with the addition of 10% Bi2O3. Mixtures were mechanochemically activated 5 and 240 minutes in a mill with ceramic balls, and sintered at temperatures from 1173-1573K. Structural transformations were determined by the XRD method. Quantitative measures of the functional sample properties, capacity Cc and electrical resistance Rρ as well as tangens of dielectric loss angle tg α were used. The results obtained proved that there is a correlation between mechanochemical activation and properties of cordierite ceramics.