Naslov
The influence of La2O3 on sol-gel derived mullite densification behavior

Autori
Mandić, Vilko ; Tkalčec, Emilija ; Kurajica, Stanislav

Vrsta, podvrsta i kategorija rada
Radovi u zbornicima skupova, cjeloviti rad (in extenso), znanstveni

Izvornik
Minerals to materials conference-M2M2008 / Nasr, Mahmoud - Kairo : CMRDI, 2008

Skup
Minerals to materials conference-M2M2008

Mjesto i datum
Kairo, Egipat, 15.12.2008. - 18.12.2008

Vrsta sudjelovanja
Predavanje

Vrsta recenzije
Međunarodna recenzija

Ključne riječi
mullite; lanthanum; sol-gel; density

Sažetak
Monophasic mullite (3Al2O3• 2SiO2) samples doped with 3.66, 7.10 and 10.29 mass% of La2O3, were prepared by a sol-gel process. Prepared gels were dried, grinded, pressed into pellets and sintered at temperatures from 1100-1600 °C for 4 h. Phase formation and densification behavior has been investigated as a function of the La2O3 content and sintering temperature. Mullite thermal evolution was analyzed by Differential Thermal and Thermogravimetric Analysis (DTA/TGA) and X-ray diffraction (XRD). The density of the sintered ceramics bodies was measured using Archimedes method. With increasing lanthanum content, the DTA peak of mullite crystallization at about 980 º ; ; C decreased in intensity, while the mullite crystallization was shifted to higher temperatures. Neither La2O3 nor La related compounds were detected by the XRD analysis for all doping levels, but beside mullite  -alumina was determined. The intensity of  -alumina diffraction peaks increased with the La2O3 doping level. The mullite unit cell parameters suggest predominant incorporation of La2O3 in the glassy phase, which quantity increased with the doping level.

Izvorni jezik
Engleski

Znanstvena područja
Kemijsko inženjerstvo

POVEZANOST RADA