| Popis: |
Cordierite (2MgO.2Al2O3.5SiO2) that is known as a high technology ceramics was produced from mechanically activated powder mixture with the intention of increasing the reactivity of substance. The powder mixture consisted of zeolite that was used as a source of silica, pure MgO, Al2O3 and ZrO2. During powder preparation, mechanical activation duration, speed of main disc and ball to mass ratio was kept constant at 60 min, 600 rpm and 20:1, respectively. After compacting of the mechanically activated powder mixture, the samples were sintered at 1250 °C for 1 h. The sintered samples were analyzed by means of X-ray diffraction (XRD) and scanning electron microscopy (SEM). The sintering behavior of the samples was determined by measuring the linear shrinkage, water absorption, density and apparent porosity. The hardness measurements were performed by using a Vickers microhardness tester under the load of 500 gf for 10 s. The density of samples ranged between 2.554 and 2.777 g/cm3 depending on ZrO2 additive. The hardness values of the undoped sample, the sample containing 10 % Zirconia and the sample containing 20 % Zirconia were found as 8.63, 9.60 and 11.9 GPa, respectively. |
