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Last name: MUÑOZ BERNABÉ
First name: Antonio
El sistema no cristalino Se100-xBix se encuadra dentro de la familia de los calcogenuros amorfos, y ha sido muy poco estudiado dada su tendencia a la separación de fases en la región de composiciones ricas en Se. Las muestras estudiadas en este trabajo ha
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Alumina and alumina/SWCNT nanocomposites have been sintered by spark plasma sintering, obtaining relative densities higher than 99%. Microstuctural characterization revealed a grain microstructure in the submicron range, where alumina/SWCNT nanocomposites exhibited a good CNTs dispersion thought the ceramic matrix. Creep experiments performed...
Muestras de α-SiC han sido sinterizadas con fase líquida (LPS) a 1950 ºC, en atmósfera de argón y tiempos de procesado entre 1 y 7 horas. Mediante microscopia electrónica de barrido (SEM) se ha caracterizado la microestructura, obteniéndose un tamaño medio de grano que aumenta con el tiempo de procesado desde 0.64 a 1.61 µm. Estas muestras han...
Effects on mechanical properties of the presence of either single-walled carbon nanotubes (SWCNTs) or multi-walled carbon nanotubes (MWCNTs) in a 3YTZP matrix have been investigated in this work. Thus, monolithic 3YTZP and 3YTZP containing 2.5 vol% either SWCNTs or MWCNTs were fabricated by Spark Plasma Sintering (SPS) at 1250 °C. Samples were...
Muestras de YTZP (policristales de óxido de circonio dopados con itria) con tamaños de grano nanométrico y diferentes cantidades de fase vítrea han sido sometidas a experiencias de fluencia en un rango de temperatura entre 1150ºC y 1200ºC, con objeto de estudiar el comportamiento mecánico de dichos materiales. Para conocer los mecanismos de...
The possibility of the influence of segregation-induced local electric fields in the bulk diffusion of the species controlling the plastic deformation of nanocrystalline materials has been pointed out. Until now, there is only a model applicable to the case of a monodimensional system. In spite of its simplicity, it predicts a significative...
Yttria tetragonal zirconia ceramic composites with 1, 2.5, 5 and 10 vol% nominal contents of graphene nanoplatelets (GNPs) were fabricated and characterized. First, the GNP dispersion in isopropanol was optimized to de-agglomerate the GNPs without damaging their structure. Then, submicrometric fully dense composites were obtained via spark...
Different colloidal powder processing routines have been used to prepare composites of 3 mol% Y2O3 -ZrO2 (tetragonal zirconia polycrystals, 3YTZP) with 2.5 vol% multiwall carbon nanotubes (MWNT) with the aim of achieving a homogeneous distribution of the MWNTs in the ceramic, eliminating agglomerates but also minimizing carbon nanotube (CNT)...
This work provides new insights on microstructure and electrical properties of 3 mol% Y2O3–ZrO2 (3YTZP) composites with 0.5, 1, and 1.5 vol% single walled carbon nanotubes (SWNTs). The composites were spark plasma sintered (SPS) in identical conditions at 1250 °C from powder prepared by two different processing routines, with the aim of...
The aim of this study is to elucidate the coarsening kinetics involved during densification of fine-grained pure α-alumina by spark plasma sintering. Low temperature and short dwell time sintering conditions were used to preserve the nanocrystalline structure of the starting commercial powder (about 50 nm). Notwithstanding the above, submicron...
The effect of single walled carbon nanotubes (SWNT) at zirconia grain boundaries on the stability of a tetragonal zirconia polycrystalline matrix has been explored in as–sintered composites and after low–temperature hydrothermal degradation (LTD) experiments. For this purpose, highly–dense 3 mol% Y2O3–doped tetragonal zirconia polycrystalline...
Dense alumina composites with different carbon nanotube content were prepared by colloidal processing and consolidated by Spark Plasma Sintering (SPS). Single-wall carbon nanotubes (SWNTs) were distributed at grain boundaries and also into agglomerates homogeneously dispersed. Carrying out Vickers hardness tests on the cross-section surfaces...
This paper is devoted to correlate the microstructure and room temperature mechanical properties of single-wall carbon nanotube (SWNT) reinforced 3. mol% yttria stabilized tetragonal zirconia with high SWNT content (2.5, 5 and 10. vol%). Fully dense composites were prepared by using a combination of aqueous colloidal powder processing and Spark...
3 mol% Yttria doped zirconia ceramics were consolidated by spark plasma sintering (SPS) at two sintering temperatures with the aim of achieving two different reduction levels. Microstructural characterization of the ceramics was performed by scanning electron microscopy (SEM). Electrical properties were investigated by means of impedance...
This work adds new experimental facts on room temperature hardness and flexural strength of alumina and composites with 1, 2, 5 and 10 vol% single-walled carbon nanotubes (SWNT) with similar grain size. Monolithic Al2O3 and composites were spark plasma sintered (SPS) in identical conditions at 1300 &Deg;C, achieving high density, submicrometric...