Los estudios relativos al empleo de métodos no-isotermos de análisis cinético de reacciones en estado sólido han experimentado un notable auge desde su iniciación a mediados del presente siglo. En nuestro Departamento se ha llevado a cabo durante los úl timos años un estudio crítico del poder de discriminación de estos métodos para establecer...
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November 22, 2016 (v1)PublicationUploaded on: December 4, 2022
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May 6, 2020 (v1)Publication
The ignition time (tig) of the mechanically induced self-sustaining reaction (MSR) process involving the formation of TiB2 from Ti/2B elemental mixtures was used to study the influence of the ratio (k = -ωv/ωd) between the rotational speed of the supporting disc (ωd) and vials (ωv) on the milling efficiency of a Pulverisette 4 planetary mill....
Uploaded on: March 27, 2023 -
September 13, 2019 (v1)Publication
In this work, a titanium–tantalum carbonitride based cermet, with cobalt as the binder phase and boron as a sintering additive, was developed by a mechanically induced self-sustaining reaction process using two different methodologies. The boron additive was added to prevent the formation of brittle intermetallic compounds generally formed...
Uploaded on: March 27, 2023 -
April 9, 2018 (v1)Publication
The kinetics of the high-temperature oxidation of titanium–tantalum carbonitride-based cermets with different Ti/Ta ratios was studied. Isothermal oxidation tests were conducted under static air for 48 h at temperatures between 700 °C and 1200 °C. The oxidation satisfied the parabolic kinetics, characteristic of the existence of a protective...
Uploaded on: December 2, 2022 -
April 17, 2018 (v1)Publication
A set of powdered cermets based on (Ti,Ta,Nb)C xN 1-x carbonitride solid solutions were synthesized from mixtures of elemental powders by a mechanically induced self-sustaining reaction (MSR) method and subsequently sintered using a pressureless method. Differing nominal compositions of the hard phase were used, and the nature of the...
Uploaded on: March 27, 2023 -
April 9, 2018 (v1)Publication
Cermets based on titanium–tantalum carbonitride were oxidized in static air between 800 °C and 1100 °C for 48 h. The thermogravimetric and microstructural study showed an outstanding reduction in the oxidation of more than 90% when the Ta content was increased. In cermets with low Ta content, the formation of a thin CoO/Co3O4 outer layer tends...
Uploaded on: March 27, 2023 -
May 7, 2018 (v1)Publication
(TixTa1-x)(C0.5N0.5)-Co-based cermets with various Ta contents (x=0, 0.01, 0.05, 0.1 and 0.2) were oxidized at 900°C for 48h in static air. A parabolic rate law, which is indicative of the formation of a protective oxide layer, was observed for all samples. The multi-layered oxide scale and the internal oxidation region that formed as the...
Uploaded on: March 27, 2023 -
April 17, 2018 (v1)Publication
Different commercial TiC-TiN/Co/Ni mixtures were used as raw materials for Ti(C,N) cermets, and the effects of the sintering parameters (binder content, binder nature, sintering time and additives) on the final hard ceramic phase were studied at the sintering temperature of 1400 °C. When Co is used as the binder medium, it is possible to...
Uploaded on: March 27, 2023 -
March 3, 2022 (v1)Publication
Muestras en polvo de Sr1-xLaxTiO3 (SLT; 0≤x≤0.5) se sintetizaron de forma rápida a temperatura ambiente vía mecano-química a partir de sus óxidos SrO, La2O3 y TiO2. Se estudió su microestructura, conductividad eléctrica y compatibilidad química, así como su potencial como material para ánodo en pilas de combustible de óxido sólido (SOFCs). Los...
Uploaded on: March 25, 2023 -
May 7, 2018 (v1)Publication
Monophase nanocrystalline powders belonging to the La 1-xSr xMnO 3±δ system (0≤x≤1) with a perovskite structure have been obtained by mechanochemistry synthesis using a planetary ball milling equipment from La 2O 3, SrO, and Mn 2O 3 mixtures. The solid state reaction was complete after one hour of milling treatment. For all the compositional...
Uploaded on: December 4, 2022 -
April 13, 2018 (v1)Publication
The formation of ZnSe via a mechanically-induced self-sustaining reaction (MSR) from a Zn/Se mixture showed that only size reduction and mixing of the reactants without product formation occurred during the induction period prior to ignition. Therefore, all mechanical energy supplied by the planetary mill during this time, called the ignition...
Uploaded on: December 4, 2022 -
April 24, 2018 (v1)Publication
Preparation of nanocrystalline ZrB2-based powder by aluminothermic and magnesiothermic reductions in M/ZrO2/B 2O3 (M = Al or Mg) systems was investigated. In this research, high energy ball milling was employed to persuade necessary conditions for the occurrence of a mechanically induced self-sustaining reaction (MSR). The course of MSR...
Uploaded on: December 4, 2022 -
April 24, 2018 (v1)Publication
Nanocrystalline zirconium diboride (ZrB2) powder was produced by mechanochemistry from the magnesiothermic reduction in the Mg/ZrO 2/B2O3 system. The use of high-energy milling conditions was essential to induce a mechanically induced self-sustaining reaction (MSR) and significantly reduce the milling time required for complete conversion....
Uploaded on: March 27, 2023 -
April 19, 2018 (v1)Publication
ZrB2-Al2O3 nanocomposite powder was produced by aluminothermic reduction in Al/ZrO2/B2O 3 system. In this research, high energy ball milling was used to produce the necessary conditions to induce a mechanically induced self-sustaining reaction. The ignition time of the composite formation was found to be about 13 min. The synthesis mechanism in...
Uploaded on: March 27, 2023 -
April 13, 2018 (v1)Publication
A ZrSiO4/B2O3/Mg/C system was used to synthesize a ZrB2-based composite through a high-energy ball milling process. As a result of the milling process, a mechanically induced self-sustaining reaction (MSR) was achieved in this system. A composite powder of ZrB2–SiC–ZrC was prepared in situ by a magnesiothermic reduction with an ignition time of...
Uploaded on: March 27, 2023 -
April 24, 2018 (v1)PublicationMechanochemical synthesis of ZrB2-SiC-ZrC nanocomposite powder by metallothermic reduction of zircon
Aluminium and magnesium were used in the M/ZrSiO4/B 2O3/C (M = Al, Mg) system to induce a mechanically induced self-sustaining reaction (MSR). Aluminium was not able to reduce the system to the desired products, and the system became amorphous after 10 h milling. However, nanocomposite powder of ZrB2-SiC-ZrC was in situ synthesized by the...
Uploaded on: December 2, 2022 -
April 19, 2018 (v1)Publication
Herein, ZrSiO4/B2O3/Mg/C system was used to synthesize a ZrB2-based composite by means of a high energy ball milling process. A mechanically induced selfsustaining reaction was achieved in this system. A nanocomposite powder of ZrB2– SiC–ZrC was prepared with an ignition time of approximately 6 minutes of milling. The role of the stoichiometric...
Uploaded on: March 27, 2023 -
April 16, 2021 (v1)Publication
La configuración tradicional de una pila de combustible de óxido sólido (SOFC), en la que se disponen materiales diferentes para cada uno de sus componentes principales (electrolito y electrodos ánodo y cátodo) se ha visto afectada recientemente por una nueva configuración de original concepto, que reúne nuevas ventajas y retos en su...
Uploaded on: March 27, 2023