The Effect of Type of the -Al2O3 Phase Stabilizer on the Properties and Weibull Modulus of Sodium -Alumina Electrolyte

In this study, Na- -alumina were synthesized via a conventional solid state reaction and the effect of the type of the -Al2O3 phase stabilizer, MgO and Li2O, on the phase formation,microstructure, electrical and mechanical properties and weibull modulus of sodium -alumina electrolyte was investigated by X-ray diffraction (XRD), scanning electron microscope (SEM), biaxial flexure (ring on ring) and ionic conductivity tests. The results indicated that the -alumina fraction of the Li2O-stabilized Na- -alumina sintered samples was about 5% higher than what can be obtained by MgO stabilizer, showing around 90% of -alumina fraction.Higher ionic conductivity of the Li2O-stabilized Na- -alumina samples can be due to its higher density, higher amount of -Al2O3 phase and larger grain size microstructure. The fracture strength and the weibull modulus of the MgO-stabilized Na- -alumina samples was higher that it can be due to the more uniform and fine-grained microstructure than Li2O-stabilized samples

Keywords:

Na- -alumina , stabilizer , phase formation , ionic conductivity , fracture strength