Title :
Ionic conductivity of eutectic mullite-zirconia fibres
Author :
Carvalho, R.G. ; Figueiredo, F.M. ; Silva, R.F. ; Costa, F.M.
Author_Institution :
Phys. Dept., Univ. of Aveiro, Aveiro, Portugal
Abstract :
Mullite-stabilized zirconia fibres were synthesized by the laser floating zone (LFZ) method. Fibres grown at 100 mm/h have fine-interpenetrating mullite-zirconia eutectic grains surrounded by an amorphous phase rich in Al, Y and Si. The crystalline phases identified by XRD are mullite with an orthorhombic crystal structure and zirconia polymorphs, occurring in the tetragonal and transformable monoclinic forms. The activation energy for the conductivity of these composites determined from Arrhenius plots between 600°C and 800°C is 1.16 eV.
Keywords :
X-ray diffraction; aluminium compounds; amorphous state; crystal structure; fibres; ionic conductivity; laser materials processing; polymorphism; solid-state phase transformations; zirconium compounds; Al6Si2O13-ZrO2; Arrhenius plots; XRD; activation energy; amorphous phase; composite materials; crystalline phase; electron volt energy 1.16 eV; eutectic mullite-zirconia fibres; ionic conductivity; laser floating zone method; monoclinic-tetragonal zirconia phase transformation; orthorhombic crystal structure; zirconia polymorphs; Ceramics; Conductivity; Conductors; Scanning electron microscopy; Solids; X-ray scattering;
Conference_Titel :
Applications of Ferroelectrics held jointly with 2012 European Conference on the Applications of Polar Dielectrics and 2012 International Symp Piezoresponse Force Microscopy and Nanoscale Phenomena in Polar Materials (ISAF/ECAPD/PFM), 2012 Intl Symp
Conference_Location :
Aveiro
Print_ISBN :
978-1-4673-2668-1
DOI :
10.1109/ISAF.2012.6297832
