Persona: García de Blas, Javier
Dirección de correo electrónico
Fecha de nacimiento
Proyectos de investigación
Unidades organizativas
Instituto Nacional de Técnica Aeroespacial
El Instituto Nacional de Técnica Aeroespacial es el Organismo Público de Investigación (OPI) dependiente del Ministerio de Defensa. Además de realizar actividades de investigación científica y de desarrollo de sistemas y prototipos en su ámbito de conocimiento, presta servicios tecnológicos a empresas, universidades e instituciones.
El INTA está especializado en la investigación y el desarrollo tecnológico, de carácter dual, en los ámbitos de la Aeronáutica, Espacio, Hidrodinámica, Seguridad y Defensa.
Puesto de trabajo
Apellidos
García de Blas
Nombre de pila
Javier
Nombre
5 resultados
Resultados de la búsqueda
Mostrando 1 - 5 de 5
Publicación Restringido Steam Oxidation Resistant Coatings for Steam Turbine Components: A Feasibility Study(Scientific.Net, 2001-10-20) Agüero, Alina; García de Blas, Javier; Muelas Gamo, Raúl; Sánchez, A.; Tsipas, Sophia A.The principal objective of the COST Action 522 is to raise the operating temperatures of both gas and steam turbines in order to increase their efficiency to reduce fuel consumption and emissions. Concerning steam turbines, the operating temperature is expected to rise from 550°C to 650°C, and the use of oxidation resistant coatings is being considered for the first time in Europe. In this preliminary work, two deposition techniques have so far been explored: slurry paints and atmospheric plasma spray (APS). Commercially available materials, known to have good oxidation resistance, were selected for both deposition techniques: one aluminium slurry and three alloyed materials for thermal spray: AlFe, FeCrAl and NiAl. The coatings were characterised by SEM-EDS and steam oxidation testing was carried out at 650°C. The preliminary findings show that some of the studied coatings may offer adequate protection.Publicación Acceso Abierto Development and Qualification of New Solid Lubricant Coatings. A Tribology Experiment at the Tribolab onto EUTEF(Centre national d'études spatiales (CNES), 2000-06-12) Oñate, J. Ignacio; Brizuela, Marta; García Luis, Alberto; Viviente, J. Luis; García de Blas, Javier; Agüero, Alina; Longo, Federico; Román, AliciaA recent study has identified that a significant number of satellite failures and anomalies, including those caused during qualification testing of mechanisms, were caused by lubrication related problems. Solid lubrication is, owing to lower vapour pressures, better boundary lubrication properties, relative insensitivity to radiation effects and wider temperature range of operation, still a preferred option for a number of space mechanisms. However, actual solid lubricants wear out and do not provide effective protection for long life mechanisms. A longer life and reduced wear debris is desirable to improve mechanism reliability. The present work reports on early results on the development of a new generation of solid lubricant coatings by the use of state of the art magnetron sputtering technology and thermal spraying processes. These coatings after a proper qualification procedure under laboratory ground conditions will be finally tested at the TriboLAB instrument that will be integrated onto the EuTEF facility at the International Space Station (ISS). Metal alloyed MoS2 solid lubricant films have been produced by a magnetron sputtering PVD process. Tribotests carried out under vacuum in a ball-on-disc tribometer with MoS2 coated AISI 440C steel discs have shown very low friction coefficients of 0.01 and long endurance, in excess of 300,000 revolutions at about a max. 0.8 GPa contact stress. These films also exhibited low friction coefficients (about 0.10) and good durability under atmospheric conditions at RT and up to 50 to 60 % RH. The thick composite lubricant coatings consisting of AlCoFeCr, NiCr, Ag and BaF2-CaF2 were deposited by plasma spray and HVOF on X-750 Ni-base superalloy. These coatings have been characterised by EDS-SEM as well as hardness measurements. The best coatings from preliminary experiments have been produced by HVOF process; these show very low porosity, a more uniform phase distribution and hardness levels of 635 HV0.2. Anticipated high temperature applications of former coatings might include elevon hinges for re-usable space planes.Publicación Restringido Thermal spray coatings for molten carbonate fuel cells separator plates(Elsevier, 2001-10-30) Agüero, Alina; García de Blas, Javier; García, M. C.; Muelas Gamo, Raúl; Román Gárate, AliciaMolten salt corrosion at the wet seal of separator plates is one of the principal life-limiting factors of molten carbonate fuel cells (MCFC). The wet seal must therefore be coated with an aluminide layer that is commonly produced by ion vapor deposition (IVD) of Al followed by heat treatment. However, this coating only lasts approximately 20 000 h and not the 40 000 h expected for a cell life. Moreover, the IVD Al coating is also very expensive since only a few plates can be coated simultaneously due to size limitations of the existing commercial vacuum chambers employed in IVD. The need of heat treatment further increases costs, particularly since it requires long heating and cooling cycles in order to minimize distortion of the thin stainless steel plates. Thermally sprayed coatings constitute an alternative that requires neither containment nor heat treatment, and also provides the possibility of depositing materials more resistant to molten carbonates than plain aluminides. However, separator plates coated by thermal spray suffer distortion, due both to sand blasting (usually required prior to coating), and to the heat transfer process that occurs during the spraying process. In this work, commercially available coatings have been applied by plasma spray and high velocity oxyfuel (HVOF), employing alternative surface preparation methods. Moreover, substrate pre-heating and/or cooling during deposition were examined in order to eliminate substrate distortion. FeCrAl, and NiAl as well as a quasi-crystalline approximant alloy AlCoFeCr were deposited on AISI 310 foils, and after optimization the resulting coatings were characterized by means of scanning electron microscopy-energy dispersive spectroscopy (SEM-EDS). The optimized coatings were then tested by immersion in a 62 mol.% Li2CO3/38 mol.% K2CO3 molten carbonate eutectic mixture at 700°C and by electrochemical impedance spectroscopy. IVD Al coatings were also tested for comparison purposes. The results indicate that FeCrAl exhibits a higher molten salt corrosion resistance than IVD aluminide coatings whereas NiAl was attacked shortly after the beginning of the test. The QC approximant AlCoFeCr resisted 1000 h of attack but its composition changed. Grinding of the substrate prior to coating resulted in good adhesion and substrate distortion was minimized by Ar cooling during deposition.Publicación Restringido Vacuum tribological behaviour of self-lubricating quasicrystalline composite coatings(Wiley, 2006-03-09) García de Blas, Javier; Román, A.; De Miguel, C.; Longo, Federico; Muelas Gamo, Raúl; Agüero, AlinaHigh-temperature-resistant self-lubricating coatings are needed in space vehicles for components that operate at high temperatures and/or under vacuum. Thick composite lubricant coatings containing quasicrystalline alloys as the hard phase for wear resistance can be deposited by a thermal spray technique. The coatings also contain lubricating materials (silver and BaF2CaF2 eutectic) and NiCr as the tough component. This paper describes the vacuum tribological properties of TH103, a coating of this type, with a very good microstructural quality. The coating was deposited by high-velocity oxygen fuel spraying and tested under vacuum using a pin-on-disc tribometer. Different loads, linear speeds, and pin materials were studied. The pin scars and disc wear tracks were characterised using a combination of scanning electron microscopy and energy dispersive spectrometry. A minimum mean steady friction coefficient of 0.32 was obtained when employing an X750 Ni superalloy pin in vacuum conditions under 10 N load and 15 cm/s linear speed, showing moderate wear of the disc and low wear of the pin.Publicación Acceso Abierto Recubrimientos protectores para componentes de turbinas de aviación y de generación de energía depositados por proyección por plasma(Elservier, 2000-07-26) Agüero, Alina; Álvarez Alba, J.; García de Blas, Javier; Valles González, M. P.Coatings produced by aluminium diffusion, called aluminide are employed to increase the oxidation and corrosion resistance, increasing the life of Ni and Co base superalloys components at temperatures comprised between 900 and 1050ºC. Consequently these coatings are frequently employed in aeronautic and power generation turbines as well as in the chemical industry. Aluminides are industrially produced by pack cementation or CVD and recently it has been demonstrated that its resistance significantly increases when Cr is added (chrome-aluminides). During this work, a feasibility study has been carried out in order to determine if plasma spray can be employed for depositing this type of coatings on turbine blades. Therefore, aluminium and aluminium/chromium layers were deposited on Ni base IN100 superalloy specimens that were subsequently subjected to a diffusion heat treatment under Ar flow. Characterisation and analysis of the coatings were carried out by metallography , SEM and EDS. Cyclic oxidation tests were carried out at 1050º C while molten sulphate hot corrosion was performed at 900º C. The results of this preliminary study are promising and indicate that plasma spray can be developed as an industrial process for production of aluminide and chrome-aluminide coatings.
Los recubrimientos producidos por difusión de aluminio, llamados aluminuros, se emplean para aumentar la resistencia a la oxidación y a la corrosión, incrementando la vida de componentes fabricados con superaleaciones de níquel y cobalto a temperaturas comprendidas entre 900 y 1050º C. Por ello se emplean muy frecuentemente en turbinas aeronaúticas y de producción de energía y en la industria química. Los aluminuros se obtienen industrialmente mediante cementación o CVD y recientemente se ha demostrado que su resistencia aumenta significativamente cuando se añade cromo (cromoaluminuros). Durante el presente trabajo, se ha realizado un estudio de viabilidad para determinar si la proyección por plasma puede ser utilizada para la producción de estos recubrimientos sobre álabes de turbina. Así pues, se depositaron capas de aluminio y aluminio/cromo sobre probetas de la superaleción base níquel IN100 que a continuación fueron sometidas a un tratamiento térmico de difusión bajo flujo de argón. La caracterización y análisis de los recubrimientos producidos se llevó a cabo mediante técnicas metalográficas, microscopía electrónica de barrido y espectroscopía de dispersión de energía de rayos X. Se realizaron ensayos de oxidación cíclica a 1050ºC y de corrosión por sulfatos fundidos a 900ºC. Los resultados de este estudio preliminar han sido muy satisfactorios e indican que la proyección por plasma puede ser desarrollada como procedimiento industrial para la producción de recubrimientos aluminuros y cromoaluminuros.
