Person: Pérez Trujillo, Francisco Javier
Universidad Complutense de Madrid
Faculty / Institute
Ingeniería Química y de Materiales
Ciencia de los Materiales e Ingeniería Metalúrgica
Now showing 1 - 10 of 10
- PublicationThe effect of microstructure evolution on the wear behavior of tantalum processed by Indirect Extrusion Angular Pressing(Elsevier, 2022-12-09) Omranpour Shahreza, Babak; Huot, Jacques; Antonov, Maksim; Kommel, Lembit; Sergejev, Fjodor; Pérez Trujillo, Francisco Javier; Heczel, Anita; Gubicza, JenőThis article studies the evolution of microstructure and the wear resistance in tantalum processed by a newly developed Severe Plastic Deformation (SPD) technique called Indirect Extrusion Angular Pressing (IEAP). The microstructure and tribological behavior of nanostructured tantalum processed by IEAP were analyzed in this work. The samples were extruded for two, five, and twelve passes of IEAP and then exposed to ball-on-disk wear testing in dry sliding conditions. It was shown that after twelve IEAP passes, an extensive grain refinement down to 500 nm was achieved, hardness increased, and a high dislocation density formed in the material. The wear resistance of the material improved successively after each pass of IEAP, and the wear rate decreased, although the friction coefficient did not change. Evaluation of the morphology of the wear tracks showed that the dominant wear mechanisms were comprised of galling, adhesive wear, pitting and microplowing. Refinement of the microstructure by IEAP led to a reduction in adhesive wear and pitting while a slight increase in oxidation appeared. Comparison of the results of wear testing between tantalum against steel balls and tantalum against alumina balls showed that the presence of alumina generated a larger portion of adhesive wear, making the wear mechanism more complicated while the tantalum-steel pair presented milder wear.
- PublicationPast research and future strategies for molten chlorides application in concentrated solar power technology(Elsevier Science BV, 2021-12-27) Lambrecht, Mickael; Miguel Gamo, María Teresa de; Lasanta Carrasco, María Isabel; Pérez Trujillo, Francisco JavierThis review summarizes past research and future strategies for the improvement of the pair heat transfer fluids (HTF) - containing material, used in concentrated solar power (CSP) plants, focusing on the most interesting and promising HTF, chloride molten salts. Indeed, their low cost and operating range temperature make them very strong potential candidates for future CSP plants, furthermore improvable by wisely adding nanoparticles. Nevertheless, their well-known aggressive behaviour entails selecting a long-lasting resistant alloy, which requires a better understanding of its associated corrosion mechanisms and the influences of its alloying elements. Mitigation strategy mechanisms that come from salt impurities implying purification processes are also reviewed. Finally, thermogravimetric analysis (TGA) coupled with differential scanning calorimetry (DSC) for salt preparation, and numerical simulations on Thermocalc software modelling elements activities of selected alloys and their interaction with molten chlorides are discussed
- PublicationComputational modelling of the local structure and thermophysical properties of ternary MgCl2-NaCl-KCl salt for thermal energy storage applications(Elsevier, 2022-07-27) Lambrecht, Mickael; Miguel Gamo, María Teresa de; Lasanta Carrasco, María Isabel; García Martin, Gustavo; Pérez Trujillo, Francisco JavierMolten salts as heat transfer fluids (HTF) for concentrated solar power (CSP) plant application are considered as the best thermal storage medium, and more precisely molten chlorides, presenting a wide operating range and coupled with competitive cost. Furthermore, MgCl2-NaCl-KCl (MgNaK) mixture appeared as the most promising one but need further studies to better understand its thermophysical properties. Indeed, its hydrated form leads to the formation of corrosive compounds. In this research, two different methods are used to model the ternary mixture. The dehydration process is evaluated by thermodynamical calculations with Thermocalc software. Then, the local structure, thermal conductivity and viscosity are estimated by means of molecular dynamics simulation, with LAMMPS package. The results were close to past simulations studies and experimental references, but discrepancies need to be further minimized regarding some variable fluctuations.
- PublicationConsumption and Emissions Analysis in Domestic Hot Water Hotels. Case Study: Canary Islands(MDPI, 2019-06-23) Díaz Pérez, Francisco; Díaz Martín, Ricardo; Pérez Trujillo, Francisco Javier; Díaz, Moises; Mouhaffel, AdibWe analyze the energy consumption of domestic hot water (DHW) in the hotels of the archipelago of the Canary Islands (Spain). Currently, systems use fossil fuels of propane and gas oil. However, this paper analyzes several alternative systems which focus on renewable and mixed energies, such as biomass, solar thermal and heat pumps systems associated with an electric generation with photovoltaic solar panels for self-consumption. The carbon footprint generated is calculated for each method of generation of DHW. In our analysis, we demonstrate that by using a high-temperature heat pump with an average coefficient of performance (COP) equal to or greater than 4.4 associated with photovoltaic solar panels, a zero-emission domestic hot water system can be achieved, when the installation area of the photovoltaic solar panels is equal to that of the solar thermal system. The importance of DHW’s carbon footprint is proven, as is the efficiency of using high-temperature heat pumps associated with photovoltaic solar panels. As such, such mixed system suggests that the generation of DHW would have zero emissions with maximum annual savings according to hotel occupancy, between 112,417 and 137,644 tons of carbon dioxide (CO2), compared to current boilers based on fossil fuels.
- PublicationCorrosion study of Ni-based alloy in ternary chloride salt for thermal storage application(Elsevier Science, 2022) Lambrecht, Mickael; García Martin, Gustavo; de Miguel Gamo, María Teresa; Lasanta Carrasco, María Isabel; Pérez Trujillo, Francisco JavierMgCl2/NaCl/KCl salt appeared as a high-potential heat transfer fluid for concentrated solar application, offering a wide operating range and low cost. Nevertheless, MgCl2 hydrates and atmosphere relative humidity are the limiting factors for a real scale CSP plant, leading to severe corrosion. Thus, Inconel 617 was tested at 700ºC up to 24 h in air atmosphere to simulate a punctual failure in the inertization system of a plant. XRD and SEM-EDX analysis showed unstable multilayers growing in cascade, highlighting chromium, aluminum, magnesium, and oxygen activities. Additionally, A radial growth of MgCr2O4 at the expense of MgO grains was visualized.
- PublicationTemperature effect and alloying elements impact on the corrosion behaviour of the alloys exposed to molten carbonate environments for CSP application(Elsevier, 2022-03-31) Miguel Gamo, María Teresa de; Lasanta Carrasco, María Isabel; García Martin, Gustavo; Díaz, Ricardo; Pérez Trujillo, Francisco JavierThis investigation assesses the effect of the alloy composition and temperature in the corrosivity of the ternary carbonate eutectic, 32% Li2CO3, 33% Na2CO3, 35% K2CO3. To this end, an iron-based alloy, coded as 51Fe-24Cr-20Ni, and a nickel-based alloy, coded as 5Fe–23Cr-58Ni-8Mo, were exposed to the carbonate mixture for 500 h at 700 ºC, 750 ºC and 800 ºC under static atmospheric air. The results revealed that corrosion extension does not have a linear dependence on temperature. There are changes in the corrosion mechanism that depend on the temperature, but, in turn, they are directly influenced by the alloying elements of the material. The performance of the nickel-based substrate proved to be catastrophic at all the studied temperatures. The order from worst to best was 700 ºC > 750 ºC > 800 ºC. The presence of a high molybdenum concentration in the carbonate mixture in contact with this nickel-based alloy suggested that this element dissolution contributes to increasing the corrosivity of the mixture. By contrast, the iron-based alloy showed improved corrosion resistance, with an estimated corrosion rate in the order of hundreds of microns at the three temperatures. The best performance of the 51Fe-24Cr-20Ni alloy was achieved at 700 ºC, followed by that at 800 ºC, while the highest degradation was registered at 750 ºC. This investigation reinforced the idea of the complexity of the corrosion processes in molten carbonate. The equilibrium of corrosive species is very sensitive to an important number of parameters, meaning that modifications in the system conditions have a great impact on corrosivity. Hence, it is critical not to make assumptions when considering potential materials for carbonate containment in CSP technology.
- PublicationExperimental study on steam oxidation resistance at 600 °C of Inconel 625 coatings deposited by HVOF and laser cladding(Elsevier, 2022-11-21) Illana Sánchez, Andrea; Miguel Gamo, María Teresa de; García Martín, Gustavo; Gonçalves, F.P.; Sousa, M.G.; Pérez Trujillo, Francisco JavierInconel 625 (IN625) coatings were deposited by High-Velocity Oxy-fuel (HVOF) and laser cladding, on a 10.50–12%Cr steel to improve its oxidation resistance. Both as-deposited coatings exhibited a γ-Ni-Cr matrix and two protective oxides (Cr2O3 and NiCr2O4). In addition, laser cladding as-deposited coatings also presented precipitates A2B-type Laves phases due to the dilution effect from laser cladding technique. Coated and uncoated steel were oxidized under isothermal conditions at 600 ◦C for 2000 h and subsequently analyzed using gravimetry, SEM-EDS and XRD techniques. The application of IN625 coatings revealed a weight gain ten times lower than that registered for the uncoated steel, this improvement being mainly due to the presence of protective and stable Cr2O3 and NiCr2O4 oxides. Additionally, the XRD analysis showed that the initial Laves phases present in the laser cladding coating, were re-dissolved and transformed in δ-Ni3Nb compound suggesting that that the temperature and exposure time are enough to induce this transformation.
- PublicationInnovaemprende(2018-07-16) De la Mata Riesco, María Isabel; Vázquez Estévez, Covadonga; De Siloniz Jiménez, María Isabel; Carballo Cuervo, Serafín; Ripio Torija, Mayte; Pérez Trujillo, Francisco Javier; Wrent, PetraEl proyecto INNOVAEMPRENDE se ha desarrollado en el contexto del Máster en Biotecnología Industrial y Ambiental, dentro de la asignatura del módulo fundamental “Organización y Seguridad Industrial” con el objetivo general de contribuir a la formación de los alumnos del Máster en la cultura del emprendimiento, favoreciendo la conciencia del valor del conocimiento dentro del ámbito de la biotecnología, sector en crecimiento que, en el contexto global de una economía cada vez más fundamentada en la I+D+i, ha demostrado su importancia e impacto económico, siendo uno de los nuevos yacimientos de riqueza económica y de empleo.
- PublicationPresentación del prototipo final a la Competición "Chem-E-Car" en el 10º Congreso Mundial de Ingeniería Química(2019-01-15) Negro Álvarez, Carlos Manuel; Monte Lara, M. Concepción; Fuente González, Elena de la; Blanco Suárez, M. Ángeles; Miranda Carreño, Rubén; Tijero Cruz, Antonio; Balea Martín, Ana; Merayo Cuevas, Noemí; Campano Tiedra, Cristina; López Expósito, Patricio Roberto; Plaza Rodríguez, Jesús; García-Ochoa Soria, Félix; Ladero Galán, Miguel; Senit Velasco, Juan José; Velasco Conde, Daniel; Pérez Trujillo, Francisco Javier; Alcalá Penadés, Germán; Mato Díaz, M. Sonia; Santos Barahona, Héctor; Lasanta Carrasco, M. Isabel; Miguel Gamo, M. Teresa de; García Martín, Gustavo; Illana Sánchez, Andrea; Bolívar Tejedo, Pilar; Carlucci, Maurizio Antonio; Morona Murillo, Lorena; Amo Salgado, Pablo del; Márquez Negro, Alejandro; Ara Jimeno, Pablo; Resino Guirao, Jesús; Alberola Sánchez, Raúl; Galán Galán, Alicia; Espinosa García, Lucía; Pedregal Sáez, Antonio; Fernández Rodríguez, Gemma; Arsuaga Cao, Pablo; Martín Jiménez, Diego; Arriba Gutiérrez, Héctor; Navarro Torres, Jorge; Sancho González, LuisEl proyecto consistió en la presentación del prototipo Chem-E-Car desarrollado en la UCM en la competición mundial que se celebró durante el transcurso del Congreso Mundial de Ingeniería Química (Barcelona, 30 septiembre-2 de octubre de 2017).
- PublicationInnovación docente para sentar las bases docentes de la competición Chem-E-Car en España(2015-02-05) Negro Alvarez, Carlos; Tijero Miquel, Julio; Blanco Suárez, Ángeles; de la Fuente, Helena; Monte Lara, Concepción; Hermosilla Redondo, Daphne; Tijero Cruz, Antonio; Merayo Cuevas, Noemi; Cortijo Garrido, Luis; Latour Romero, Isabel; López Expósito, Patricio; Barndok, Helen; Blanco Jaen, Laura; Balea Martín, Ana; Plaza Rodriguez, Jesus; García Ochoa, Félix; Ladero Galán, Miguel; Guijarro Gil, Isabel; Esteban Serrano, Jesús; Ravelo Velasquez, Marianela; Ripoll Morales, Vanessa; Rodríguez Martín, Alberto; Wojtusik, Mateuzs; Pérez Trujillo, Francisco Javier; Mato Díaz, Sonia; Alcalá Penadés, German; Morena López, Susana de la; Santos Barahona, Héctor; Lasanta Carrasco, M. Isabel; García Martin, Gustavo; de Miguel Gamo, TeresaDesarrollo de herramientas docentes para la adquisición de la capacidad de controlar de forma segura una reacción química, concibiendo, diseñando y ejecutando un sistema cumpliendo los estándares de seguridad y medioambientales. Las herramientas desarrolladas son de aplicación a un posible implantación de la competición desarrollada por AIChE: "Chem-E-Car".