The members of the group have expertise and facilities at ICMM, and at collaborating institutions, to work with the following techniques:
Processing
of piezoelectric ceramics with controlled microstructures (milling of precursors, sol-gel, Pechini, pressing powders, electrical furnaces for sintering in air and hot-pressing (up to 1000 ºC and 100 MPa), laboratory for cutting (diamong saw and hollow diamond drill bits), polishing and electroding ceramic samples and for electrical poling of the samples (HV supplies and silicone oil bath and HV sampleholders; Berlincourt d33-meter))
See examples in:
A. Reyes-Montero, L. Pardo, R. López-Juárez, A.M. González, S.O. Rea-López, M.P. Cruz and M.E. Villafuerte- Castrejón Sub-10µm grain size Ba1-xCaxTi0.9Zr0.1O3(x=0.10 and 0.15) piezoceramics processed using a reduced thermal treatment Smart Materials and Structures 24, 065033 (2015)
L. Pardo, A. Garcia, K. Brebøl, E. Mercadelli and C. Galassi
Piezoelectric properties of lead-free submicron-structured (Bi0.5Na0.5)0.94Ba0.06TiO3 ceramics from nanopowders Smart Mater. Struct. 19, 115007 (2010)
Crystal structure
determination of piezoceramics by both conventional and synchrotron (SSRF(USA) and Elettra (IT)) X-ray diffraction, under in-situ applied electric-field.
See examples in:
L.E. Fuentes-Cobas, M.E. Montero-Cabrera, L. Pardo and L. Fuentes-Montero
Ferro-piezoelectrics under the synchrotron light: a review Materials, 9(1), 14(34pp) (2016)
A.M. Gonzalez, L. Pardo, M.E. Montero-Cabrera and L.E. Fuentes-Cobas
Analysis of the rhombohedral and tetragonal symmetries coexistence in lead-free 0.94(Bi0.5Na0.5)TiO3 – 0.06 BaTiO3 ceramics from nanopowders Advances in Applied Ceramics Structural, Functional and Bioceramics 115(2), 96-105 (2016)
Microstructure
determination of piezoceramics by computer assisted (software MIP45) quantitative microscopy (SEM or optical (Laborlux 12 ME ST with light source and digital camera)).
See details and applications of the technique in the processing optimization:
L. Pardo, A. García, K. Brebøl, E. Mercadelli and C. Galassi
Enhanced properties for ultrasonic transduction, phase transitions and thermal depoling in 0.96(Bi0.5Na0.5)TiO3-0.04BaTiO3 submicron structured ceramic J. Phys. D: Appl. Phys 44, 335404 (2011)
A. Moure, T. Hungría, A. Castro, L. Pardo
Quantitative Microstructural Analysis and Piezoelectricity of Highly Dense, Submicron-Structured NaNbO3 Ceramics from Mechanically Activated Precursors J. Eur. Cer. Soc. 29, 2297-2308 (2009)
Mechanical
properties study by indentation techniques (micro- and nano-hardness tester (NHT) (CSM instruments), the latter in-house modified for in-situ applied electric-field and vice-versa electrical measurements under a mechanical load. See at:
D. Rivero, A. García and L. Pardo
Modification of a Commercial Nanoindentation System for Measurement of Hysteresis Cycles Under Mechanical Load in Polycrystalline Ferroelectric Films Bol. Soc. Esp. Ceram. Vidr. 51 (1), 12-19 (2012)
Piezoelectric
properties study by in-house developed software for determination of piezoelectric, dielectric and elastic complex coefficients in the linear range from the electromechanical resonance modes of poled ferroelectric ceramics by complex impedance measurements (HP4194A (1kHz-40MHz), HP4192A(5Hz-13MHz) and HP4191A RF (1-1000MHz) up to T>500ºC.
See the use in the matrix characterization for reliable and accurate FEM of ceramic resonators in,
L. Pardo, F. Montero de Espinosa, A. García and K. Brebol
Choosing the best geometries for the linear characterization of lossy piezoceramics: Study of the thickness poled shear plate Applied Physics Letters 92 , 172907 (2008).
See the use for study of ferroelectric-relaxor or ferro-antiferroelectric phase transitions in,
L. Pardo, A. García, K. Brebøl, E. Mercadeli and C. Galassi
Characterization of Nanostructured Phases and Peculiar Phase Transitions in BNBT Lead-Free Piezoceramics Advances in Science and Technology, 90, 12-18(2014)
A. Moure, T. Hungria, A. Castro and L. Pardo
Microstructural effects on the phase transitions and the thermal evolution of elastic and piezoelectric properties in highly dense, submicron structured NaNbO3 ceramics Journal of Materials Science 45, 1211–1219 (2010)
Dielectric, Ferroelectric and Pyroelectric
properties study at the electrical measurements lab for the macroscopic characterization of ceramics, including bipolar programable Amplifier Kepco BOP 1000M, oscilloscope Tektronics TDS520/A1, Agilent programmable waveform generators, electrometers, probe stations (cryogenic, high-temperature), etc.
F. L. Martínez, J. Hinojosa, G. Domenech, F. Luque, J. Zapata, R Ruiz and L. Pardo.
Dielectric Constant Tunability at Microwave Frequencies and Pyroelectric Behavior of Lead-Free Submicron-Structured (Bi0.5Na0.5)1-xBaxTiO3 Ferroelectric Trans. IEEE UFFC 60 (8), 1595 (2013)
L. Pardo, E. Mercadelli, A. García, K. Brebøl and C. Galassi.
Field-Induced Phase Transition and Relaxor Character in Submicron Structured Lead-Free (Bi0.5Na0.5)0.06Ba0.94TiO3 Piezoceramics at the Morphotropic Phase Boundary IEEE Trans. UFFC, 58(9), 1893-1904 (2011)
Members also have access to other techniques and scientific services of the ICMM.
