Browsing by Author "Marcos, J."
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Item Advanced packaging for GaN high power electronics(2008) Marcos, J.; Cobo, I.; Barcena, J.; Maudes, J.; Amado, R.; Vellvehi, M.; Jorda, X.; Obieta, I.; Guraya, C.; Bilbao, L.; Jiménez, C.; Coleto, J.; Tecnalia Research & Innovation; EXTREMAT; PRINTEX; MercadoDevices based on wide-bandgap semiconductors such as SiC or GaN allow high power densities and elevated working temperatures. Here we present an innovative package for high-power electronics, within the framework of an ESA-contracted project. The housing concept, design study, materials selection, manufacturing method and first test results are the parameters to be followed in order to get this innovative electronic package. Materials are selected for their high thermal conductivity (TC) and low coefficient of thermal expansion (CTE). Several materials were selected: A1N was selected as substrate material, and novel metal-matrix composites (MMCs) based on Cu-Diamond were evaluated as heat-sink materials. Determination of the final dimensions of the housings according to the new design was required to get a complete bonding. This new heat sink geometry has been validated and the new components fabrication has been already started. An improved surface quality has been achieved, which will increase the contact between the heat sink and the aluminum spreader for electrical characterization. Subsequently, a complete bonding study between ceramic materials and the MMCs was performed. Determination of the final dimensions of the housings according to the new design was required to get a complete bonding. This new MMCs heat sink geometry has been validated and the new components fabrication has been selected. An improved surface quality has been achieved, which will increase the contact between the heat sink and the aluminum spreader for high temperature electrical characterization. In order to obtain fully dense materials A1N was manufactured by pressureless sintering, while the MMCs parts were manufactured by hot-pressing. The MMCs powders were obtained by an electroless plating process. Preliminary characterization of the housing and its parts show encouraging results as a solution for high-power devices working at temperatures up to 400 °C. TC near 500W/mK and CTEs of around 10 ppm/K have been obtained. These are comparable to the stateof-the-art materials. Out-gassing, thermal cycling and hermeticity tests of the packages and high temperature electrical characterization of the electronic paths and global package were performed. The presented new packaging solutions are showing great promise for space applications such as high-frequency power amplifiers for satellite communications and for radar transmitters, and have started to generate an interest from commercial space-system manufacturers.Item Alternative rigidisation method for inflatable structures(2008) Markaide, N.; Marcos, J.; Zubillaga, O.; Tecnalia Research & Innovation; SISTEMAS FOTOVOLTAICOSThermally rigidised thermoset composites and UV rigidised composites are methods that have been widely studied in inflatable structures. However, these methods based on chemical rigidisation present some awbacks, as for example the influence of space environment in polymerisation and thus, in final properties obtained in the composite. Alternative and promising methods are passive cooled thermoplastics. The aim of this project has been to conduct further research in this new rigidisation technology. A study of different materials has been performed based on the final properties required in space conditions, but also properties specifically needed for folding, inflation and rigidisation steps. Thus, the approach has been planned in two phases. The first phase covers a material study and testing at coupon level, which has allowed the optimisation of the rigidisation process. The second phase deals with the manufacturing, testing and validation of a reduced size breadboard, consisting of a solar array composed by two lateral flexible solar panels (membranes) supported by a central rigidisable boom.Item Compact fixturing based on magneto-rheological fluids for aeronautic stringers milling(2010) de la O Rodríguez, M.; Collado, V.; Böse, H.; Gerlach, T.; Würtz, T.; Holz, B.; May, C.; Thoelen, J.; Porras, E.; Marcos, J.; Ionescu, M.; ROBOTICA_AUTOMA; MAQUINASThe paper explains the compact fixturing based on magneto-rheological (MR) fluids that have been designed and validated for aeronautic stringers milling. The MR fluid based tooling developed is flexible and reconfigurable as it can be adapted to different profile's lengths and sections and it is able to fix compliant workpieces without reference faces as the MR fluid adapts to the outer shape of each profile. The MR fluid based tooling is suitable to hold non-magnetic materials such as aluminum and also materials that do not admit high clamping forces, such as titanium, because they will appear as deformation after machining due to the memory effect of titanium. The MR fluid based tooling has been tested in a machine environment under real machining conditions and promising results have been obtained.Item Electron beam curing for manufacturing of high dimensionally stable cfrp structures like space telecommunication satellite antenna reflectors(American Institute of Aeronautics and Astronautics Inc., 2006) Marcos, J.; Mezzacasa, R.; Segura, M.; Tecnalia Research & Innovation; COMPOSITEThe final main objective of this project has been to develop a high dimensionally stable composite antenna sub reflector for specific space telecommunication satellite applications working in the range of 40/50GHz. This specification requires very high dimensional accuracy which has been quantified with a target of a maximum error in the range of 10-40 microns RMS over the functional surface of the reflector. In this context, this paper describes the materials selection, manufacturing and testing activities carried out at specimen level in order to complete the evaluation and comparison of Electron Beam cured samples versus the Autoclave cured ones in order to analyse the feasibility and advantages of using this alternative curing process. The expected benefits correspond to the fact of using low temperature curing techniques with lower dimensional distortion due to the CTE effect of the structure material and the tooling. This paper includes the description of the test set-up, procedure, results and the evaluation of the results. According to the results obtained, regarding the space environment conditions behaviour, no significant differences are found between the EB material option and the thermal curing solution. Mechanical properties, CTE and outgassing properties are similar. The adhesion performed tests on the metallic coated specimens show also similar performance. Therefore, the electron beam cured material is a promising solution for this application. This activity has been developed within the research project 'Hybrid mechanical-electronic pointing system', under ESA contract 18186/04/NL/CH.Item High performance ceramic discharge chambers(American Institute of Aeronautics and Astronautics Inc., 2006) Caro, I.; Ahedo, E.; Guraya, C.; Landaberea, A.; Marcos, J.; PROMETAL; EXTREMAT; Tecnalia Research & InnovationThe work presented focuses on the development of one of the critical components of a stationary Plasma Hall Effect Thruster, the discharge chamber or accelerating channel. A global approach is being performed. It has been initiated by analyzing the various discharge chamber configurations adopted by different applications using HET, leading to a detailed assessment of the applicable requirements for HET discharge chambers. Scaling up and down being one of the major targets of the activity, a complete discussion of the requirements of such a component has been done and also how those requirements are affected by the currently envisaged up and down scaling of the current HET technology. The limitations of the current chamber manufacturing technology has also been reviewed together with an assessment of alternative technologies that can be appropriate candidate for up and down scaling issues. From an experimental point of view, different up and down scaled (5KW / 90 W) HET units have been selected as target for closely studying and manufacturing the corresponding chambers. Some numerical simulations of the contained plasma and the resulting thermal situation along those particular ceramic components have been performed and closely discussed. Starting from the current state-of-the-art technology based on hot-pressing and final machining of BN-SiO2 materials, the manufacturing steps have being optimized and some novel compositions with enhanced properties have also being developed. Finally, a complete characterization of the produced materials has been performed focusing on the ion sputtering behaviour of the different material compositions being studied. A laboratory experimentation procedure capable of detecting behaviour differences is being set-up, and here a reported some of the preliminary results.Item Intermetallics for thermal protection systems(2009) Marcos, J.; Tecnalia Research & InnovationFuture Reusable Launch Vehicles (RLV's) will require improved Thermal Protection Systems (TPS) to achieve the ambitious goal of reducing the cost of delivering a payload to orbit by, at least, an order of magnitude. In this context, metallic materials are good candidates for their use in TPS and hot structures. Up to date, only two major type of materials have been considered and developed in Europe for such type of applications: Oxide Dispersion Strengthened (ODS) and intermetallics (?-TiAl). INASMET, during last years, has been working with the orthorhombic titanium aluminides, whose specific properties are comparable, to those of ODS and ?-TiAl materials. The EXPERT mission represents a unique opportunity to test under re-entry conditions this material.Item Multifunctional equipment design by using high thermal conductivity fibres(2005) Marcos, J.; Segura, M.; Antolin, J. C.; Landaberea, A.; Lamela, F.; Atxaga, G.; Tecnalia Research & Innovation; COMPOSITE; ROBOTICA_AUTOMA; EXTREMATA new equipment housing and satellite platform design concept has been developed, the so-called, Multifunctional Structures MFS. The MFS integrates thermal, electrical, mechanical and radiation shielding functionalities under the same structure by using flexible circuits, lightweight structures, shielding concepts and high thermal conductivity pitch fibres, acting as thermal doublers integrated onto the structural sandwich. As demonstrator concept, the Data Handling Unit (DHU) of PROTEUS Minisat bus was identified. During the re-engineering design, manufacturing and testing have been performed. Several aspects as materials, assembly and shielding have been studied. This project has allowed assessing the potentialities of using the MFS concept for equipment housings of future space missions. The work has been carried out under ESA GSTP contract 16725/02/NL/CK "Advanced Equipment Design", following a multi-partners collaborative approach miniproject. Under the same project technological samples and breadboards for equipment housings of ADPMS PROBA2 satellite, improved integrated design of INMARSAT equipment and T/R Modules of the electronic boxe s for SAR antenna have been designed, manufactured and tested.Item Nanocomposites in multifuctional structures for spacecraft platforms(2012) Marcos, J.; Mendizabal, M.; Elizetxea, C.; Florez, S.; Atxaga, G.; Del Olmo, E.; Tecnalia Research & Innovation; POLIMEROS; EXTREMATThe integration of functionalities as electrical, thermal, power or radiation shielding inside carrier electronic boxes, solar panels or platform structures allows reducing weight, volume, and harness for spacecraft. The multifunctional structures represent an advanced design approach for space components and subsystems. The development of such multifunctional structures aims the re-engineering traditional metallic structures by composites in space, which request to provide specific solutions for thermal conductivity, EMI-EMC, radiation shielding and integration. The use of nanomaterials as CNF and nano-adds to reinforce composite structures allows obtaining local solutions for improving electrical conductivity, thermal conductivity and radiation shielding. The paper summarises the results obtained inof three investigations conducted by Tecnalia based on carbon nanofillers for improving electro-thermal characteristics of spacecraft platform, electronic substrates and electronics boxes respectively.Item Novel electronic packages made of highly loaded SiC particle aluminium based composites for space applications(2003) Coleto, J.; Maudes, J.; Goñi, J.; Marcos, J.; Calvin, J.; Costas, F.; Mercado; PRINTEX; Centros PRE-FUSION TECNALIA - (FORMER); Tecnalia Research & InnovationA novel method for manufacturing AMC based packages for Monolithic Microwave Integrated Circuits (MMIC) applications has been developed by INASMET FOUNDATION and MIER COMUNICACIONES S.A. for space applications. Major problems associated to conventional Kovar or Copper Tungsten packages for electronic applications are poor heat dissipation and heavy weight. Based on the increasing need for high power dissipation and higher electronic components density in electronic devices for space applications (Phase arrays, etc), the present work has targeted the development of a new manufacturing process of multicavity packages made of aluminium matrix composites (AMCS) highly loaded with SiC particles, in which heat dissipation is notably increased and weight is lowered. Manufacturing method and new AMCS are more competitive in terms of properties/price ratio, in comparison with similar materials presently produced by metal infiltration techniques, due to the simplicity and high productivity of the novel shaping technology developed. Multicavity packages and cover lids were manufactured through a near net shape technology. Machining to net shape is performed with PCD tools to get requirements of finishing. A double Ni/Au electroplating is performed on the packages before integration of hybrid microwaves and package closing. External visual inspection, electrical and thermal resistance measurements are performed in order to confirm the validity of hybrid microwaves integration.Item Radiation shielding of composite space enclosures(2012) Atxaga, G.; Marcos, J.; Jurado, M.; Carapelle, A.; Orava, R.; EXTREMAT; Tecnalia Research & InnovationSpace electronic systems employ enclosures to shield sensitive components from space radiation. The purpose of shielding is to attenuate the energy and the flux of ionizing radiation as they pass through the shield material, such that the energy per unit mass (or dose) absorbed in silicon is sufficiently below the maximum dose ratings of electronic components. The received radiation amount varies significantly depending on several variables that include mission parameters (orbit, altitude, inclination and duration), spacecraft design (spacecraft wall thickness and panel-enclosure location). To achieve the optimum shielding with the minimum weight, all these variables have to be considered in the design. Energetic particles, mainly electrons and protons, can destroy or cause malfunctions in spacecraft electronics. The standard practice in space hardware is the use of aluminium as both a radiation shield and structural enclosure. Composite structures show potential for significant mass savings. However, conventional graphite epoxy composites are not as efficient shielding materials as aluminium because of their lower density, that is, for the same mass, composites provide 30 to 40% less radiation attenuation than aluminium. A solution is to embed high density (atomic weight) material into the laminate. This material, typically metallic material, can be dispersed in the composite or used as layers in the laminate (foils). The main objective of the "Radiation Shielding of Composite Space Enclosures" (SIDER) project is the development of the technologies and tools required to obtain lightweight, safe, robust and reliable composite structures. Two different strategies are being analysed as alternatives for radiation shielding: and he incorporation of a high density material foil. This paper will present and analyse the radiation shielding obtained by the incorporation of nanomaterials in composite structures.Item Smart thermal protection systems(2008) Marcos, J.; Coleto, J.; Adarraga, O.; Tecnalia Research & Innovation; Mercado; PRINTEXSmart materials and systems could represent an interesting alternative to current TPS for future RLVs(reusable launch vehicle). Smart systems can be defined as systems able to "feel" their thermomechanical environment and to change their basic physical properties to "react or adapt" to the environment so that the effects are reduced. A ESA Contract work has been performed by INASMET-TECNALIA to study smart TPS concepts based on EVEREST SSTO laucher specifications. The identification of smart concepts, study their feasibility and selection by comparison to a selection criteria list. The Smart active TPS studied were: Sensor/actuator to vibration damping control by piezoceramics able to sustain 650oC. TPS Health monitoring within piezoelectric based on emitted/received microvibrations. Actuation (moving, tilting, owering) "morphing" tiles for aerothermodynamic changes. TPS monitoring: thermal sensitive coatings. Phase change materials for temperature control (hot/cold parts attachments). In situ repair: Selfhealing materials (micro-capsules dispersed on metallic parts, doped ceramics to react with oxygen producing glasses) Materials with adaptable properties (FGM) functional graded materials Adapting CTE on stand-offs. Tailoring thermal conductivity A proof-of-concept of the two most promising smart concepts selected were manufactured and evaluated on representative environment.Item Space propulsion components based on Gamma TiAl based alloys by combustion synthesis + compation route(International Astronautical Federation, IAF, 2008) Agote, I.; Marcos, J.; Lagos, M.; Pambaguian, L.; EXTREMAT; Tecnalia Research & InnovationIntermetallic compounds of Ti-Al system and alloys based on such compounds are materials of rapidly growing technological importance. Such alloys have relatively high yield strength at elevated temperatures, advanced creep characteristics, and good oxidation/corrosion resistance. Several methods have been utilized in the synthesis of Ti-Al intermetallic compounds. These include conventional melting and casting processes and powder metallurgical techniques. The latter include mechanical alloying, plasma-rotating electrode processes, and inert gas atomization (which all have been recently proposed as methods of preparing titanium aluminides in powder form). In all of these approaches, a subsequent step is required to obtain products with the desired density and shape. Over past years, a search for new synthetic approaches to intermetallides (including titanium aluminide and related materials) has led, among others, also to the technique of Self-propagating High-temperature Synthesis (SHS). This is an alternative powder technique for the production of intermetallics. This process requires a large exothermic enthalpy of formation for the desired intermetallic compound. Because of a low caloricity of reaction between Ti and Al, the classical SHS reaction between these metals can be initiated only upon preliminary heating of a green mixture. For this reason, the best results in synthesis of titanium aluminides were attained by combining SHS with some kinds of internal influence, such as heating up to the ignition temperature, mechanoactivation of green mixture, SHS followed by hot isostaic pressing (HIP), SHS in electromagnetic field, etc. This work studied and optimized the SHS-densification route for the synthesis of Gamma TiAl based Intermetallic (GE alloy: 48Ti-48Al-2Cr-Nb) using two different combustion modes: forced SHS + compaction and thermal explosion + compaction. A complete metallurgical characterization of the product was done: phase analysis, density, chemical analysis, microstructure and mechanical properties (tensile strength). The developed material and manufacturing process is a potential candidate to be used as turbine blades for ARIANNE VULCANE engine.