Mechanical Properties of LSGM as an Electrolyte for Solid Oxide Fuel Cells

Strontium- and magnesium-doped lanthanum gallate (LSGM) due to its high ionic conductivity and chemical stability over a wide range of oxygen partial pressures and temperatures has been considered as an alternative electrolyte for solid oxide fuel cell (SOFC) systems. Mechanical properties of LSGM electrolyte layer however need to be well studied. An overview of mechanical behavior of LSGM on an all-perovskite SOFC is presented in this work. Dense La_0.8Sr_0.2Ga_0.7Mg_0.3O_2.8 electrolyte pellets were studied. Mechanical properties, such as hardness, elastic modulus, fracture toughness, and modulus of rupture (MOR) of the electrolyte pellets at different sintering temperatures were measured and correlated with the SEM morphological characterization. Samples sintered for 2h at 1500°C demonstrated slightly enhanced mechanical properties than those sintered at 1450°C and 1400°C.