CETMIC   05378
CENTRO DE TECNOLOGIA DE RECURSOS MINERALES Y CERAMICA
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
Mechanical behavior of lanthanum silicate oxyapatite
Autor/es:
GUSTAVO SUAREZ; NICOLAS M. RENDTORFF; YOSHIO SAKKA; MOREIRA TOJA, RAMIRO J.; ESTEBAN AGLIETTI; TETSUO UCHIKOSHI
Lugar:
Foz de Iguazu
Reunión:
Congreso; ICC7. 7th International Congress on Ceramics; 2018
Resumen:
Lanthanum silicate oxyapatites (LSO) are ceramic materials that show a good electric conduction at intermediate temperatures (600 ~ 800 ºC). Interest in this kind of materials is related to the need for lower operation temperatures of solid oxide fuel cells (SOFCs), which would bring operational and maintenance costs down. It is desirable that solid electrolytes possess adequate mechanical properties to avoid cracking during operation and to assure a desirable performance [1,2]. Apatyte-structured lanthanide silicates have been poorly described in relationship to their mechanical properties. In this work, we address this vacancy.LSO was synthesized per a solid state reaction method [3]. Rectangular cross-section bars were prepared by grinded powder, uniaxially pressed at 50 MPa and further isostatically pressed at 100 MPa. Casted bars were dried at 110 ºC for 24 hs and fired with a heating rate of 5 ºC/min and 2 hours dwells at temperatures of 1100, 1200, 1300, 1400 and 1500 ºC. Fired bars porosity and density were studied via Archimedes method. Stress-strain curves from three point flexion arrangements were studied to obtain Young?s modulus and its flexural strnght. Besides, Young?s modulus was also measured and compared via impulse excitement method. Microhardness was studied with a Vickers indenter, and nanohardness of the pieces sintered at 1500 ºC was studied with a Berkovich indenter. LSO presents lower mechanical properties if we compare these results with the traditionally used cubic yttria-stabilized zirconia, but the mechanical behavion showed in this work that this new material could be usefull for Solid Oxyde Fuell Cells.