Browsing by Author "Guraya, C."
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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 Bi-propellant micro-rocket engine(2004) Miotti, P.; Tajmar, M.; Guraya, C.; Perennes, F.; Marmiroli, B.; Soldati, A.; Campolo, M.; Kappenstein, C.; Brahmi, R.; Lang, M.; EXTREMATMicro-satellites (from 10 kg up to 100 kg) have mass, volume, and electrical power constraints due to their low dimensions. These limitations lead to the lack in currently available active orbit control systems in micro-satellites. Therefore, a micro-propulsion system with a high thrust to mass ratio is required to increase the potential functionality of small satellites. Mechatronic is presently working on a liquid bipropellant micro-rocket engine under contract with ESA (Contract No.l6914/NL/Sfe - Microturbomachinery Based Bipropellant System Using MNT). The advances in Mechatronic's project are to realise a micro-rocket engine with propellants pressurised by micro-pumps. The energy for driving the pumps would be extracted from a micro-turbine. Cooling channels around the nozzle would be also used in order to maintain the wall material below its maximum operating temperature. A mass budget comparison with more traditional pressure-fed micro-rockets shows a real benefit from this system in terms of mass reduction. In the paper, an overview of the project status in Mechatronic is presented.Item Bi-propellant micro-rocket engine(2004) Miotti, P.; Tajmar, M.; Guraya, C.; Perennes, F.; Marmiroli, B.; Soldati, A.; Campolo, M.; Kappenstein, C.; Eloirdi, R.; Lang, M.; EXTREMATMicro-satellites (from 10kg up to 100kg) have mass, volume, and electrical power constraints due to their low dimensions. These limitations lead to the lack in currently available active orbit control systems in micro-satellites. Therefore, a micro-propulsion system with a high thrust to mass ratio is required to increase the potential functionality of small satellites. Mechatronic is presently working on a liquid bipropellant micro-rocket engine under contract with ESA (Contract No.16914/NL/Sfe - Microturbomachinery Based Bipropellant System Using MNT). The advances in Mechatronic's project are to realise a micro-rocket engine with propellents pressurised by micro-pumps. The energy for driving the pumps would be extracted from a micro-turbine. Cooling channels around the nozzle would be also used in order to maintain the wall material below its maximum operating temperature. A mass budget comparison with more traditional pressure-fed micro-rockets shows a real benefit from this system in terms of mass reduction. In the paper, an overview of the project status in Mechatronic is presented.Item Binder jetting of high dimensional stability alloy for space applications(European Powder Metallurgy Association (EPMA), 2020) Azurmendi, N.; Lores, A.; Guraya, C.; Agote, I.; EXTREMATBinder Jetting technology provides a new scope in metal additive manufacturing due to its capability to produce high complexity parts in a wide variety of different materials. This work opens a new pathway to fabricate high dimensional stability Invar36 aerospace devices with Binder Jetting technology, for applications where temperature fluctuations directly interfere in the correct performance of high sensibility systems. Since full density part fabrication is one of the main ongoing challenges for Binder Jetting, the leading objective of this work is to study and optimise the main process parameters to increase the final density of Invar36 printed parts. Microstructural analysis and obtained density and CTE values, confirmed the feasibility to fabricate Invar36 parts.Item Binder jetting process effects on metal powder reusability(European Powder Metallurgy Association (EPMA), 2019) Agote, I.; Azurmendi, N.; Guraya, C.; Lores, A.; EXTREMATDue to its high cost and its direct impact in final part properties, the reuse of metal powders for additive manufacturing purposes is being a trending subject of study. In order to reduce production costs, ensure a robust process quality management, and consolidate a widespread industry adoption of Additive Manufacturing (AM) technology, the analysis and control of the effect that multiple process cycles have on powder raw material is crucial. To this aim, a starting virgin 316L powder was subjected to a number of Binder Jet printing and curing cycles, simulating large size production lots. The powder particle size distribution, oxide content and powder contamination was analysed along with the sinterability of some control specimens printed between certain number of process cycles. Results showed that, unlike in other powder bed based AM technologies, the reuse of powder material in Binder Jetting process has a minimum influence on raw powder and final part density.Item Development of Powder Injection Moulding Process of Cobalt Free Diamond Composite for Cutting Tool Applications(European Powder Metallurgy Association (EPMA), 2020) Agote, I.; Guraya, C.; Colella, A.; Nicolis, E.; Dai Prè, M.; EXTREMATNowadays, diamond blades and wires are commonly used for sawing natural stone, concrete and ceramics. The cutting section of the tool consists of synthetic diamond crystals embedded in a metallic matrix, obtained using powder metallurgical (PM) routes: the most common route includes the hot pressing of the composite to obtain a fully dense part. This process has some limitations in terms of achievable part geometrical complexity and process productivity. In addition, the most commonly used metallic matrix is cobalt, which besides its proven high toxicological risk (REACH legislation), it is considered as a critical raw material (CRM) by the European Union. The present work has a twofold objective: from one side the substitution of cobalt by other non-toxic elements, and at the same time, the development of a powder injection moulding process to allow obtaining more complex shape parts (thus improving their performance) and increasing the process productivity.Item An effective thermal conductivity measurement system(2004-11) Madrid, F.; Jordà, X.; Vellvehi, M.; Guraya, C.; Coleto, J.; Rebollo, J.; EXTREMAT; MercadoIn the technical literature, there is a lack of reliable thermal parameters and, often, it is necessary to do in situ measurements for every particular material. An effective thermal conductivity measurement system has been designed and implemented to provide reliable and accurate values for that thermal parameter. The thermal conductivity of a given material is deduced from thermal resistance differential measurements of two samples. All parts of the implemented system as well as practical and theoretical solutions are described, including a power controller circuit exclusively conceived for this application. Experimental considerations to reduce the measurement error are exposed, as well as some results obtained for three different materials.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 Innovative packaging solution for power and thermal management of wide-bandgap semiconductor devices in space applications(American Institute of Aeronautics and Astronautics Inc., 2006) Barcena, J.; Merveille, C.; Maudes, J.; Vellvehi, M.; Jorda, X.; Obieta, I.; Guraya, C.; Bilbao, L.; Jiménez, C.; Coleto, J.; EXTREMAT; PRINTEX; Tecnalia Research & Innovation; 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 paper shows the housing concept, design study, materials selection, manufacturing method and first test results. Materials are selected for their high thermal conductivity (TC) and low coefficient of thermal expansion (CTE). Several materials were selected: AlN was selected as substrate material, and novel metal-matrix composites (MMCs) based on Cu-Diamond and CuVapour Grown Carbon Nanofibres (VGCNFs) were evaluated as heat-sink materials. Subsequently, a complete bonding study between ceramic materials and the MMCs was performed. In order to obtain fully dense materials AlN 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 characterisation of the housing and its parts show encouraging results as a solution for high-power devices working at temperatures up to 300 °C. TC near 500W/mK and CTEsof around 10 ppm/K. have been obtained. These are comparable to the state-of-the-art materials. Out-gassing, thermal cycling and hermeticity tests of the packages were performed. The presented new packaging solutions are showing great prorrise 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-systemmanufacturers.Item Innovative packaging solution for power and thermal management of wide-bandgap semiconductor devices in space applications(2008-03) Barcena, J.; Maudes, J.; Vellvehi, M.; Jorda, X.; Obieta, I.; Guraya, C.; Bilbao, L.; Jiménez, C.; Merveille, C.; Coleto, J.; EXTREMAT; PRINTEX; Tecnalia Research & Innovation; 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 paper shows the housing concept, design study, materials selection, manufacturing method and first test results. Materials are selected for their high thermal conductivity (TC) and low coefficient of thermal expansion (CTE). Several materials were selected: AlN was selected as substrate material, and novel metal-matrix composites (MMCs) based on Cu-diamond and Cu-vapour grown carbon nanofibres (VGCNFs) were evaluated as heat-sink materials. Subsequently, a complete bonding study between ceramic materials and MMCs was performed. In order to obtain fully dense materials AlN was manufactured by pressureless sintering, while the MMC parts were manufactured by hot-pressing. The MMC powders were obtained by an electroless plating process. Preliminary characterisation of the housing and its parts show encouraging results as a solution for high-power devices working at temperatures up to 300 °C. TC near 500 W/mK and CTEs of around 10 ppm/K have been obtained. These are comparable to the state-of-the-art materials. Out-gassing, thermal cycling and hermeticity tests of the packages were performed. The presented new packaging solutions show 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 Preliminary comparison of hardmetals obtained by SPS and by electrical resistance sintering (ERS)(European Powder Metallurgy Association (EPMA), 2014) Gallardo, J. M.; Montes, J. M.; Schubert, Th; Weissgaerber, T.; Andreouli, C.; Oikonomou, V.; Prakash, L.; Calero, J. A.; Abrivard, G.; Guraya, C.; Lagos, M. A.; Agote, I.; EXTREMATCutting tools with improved properties and using a new processing method are being developed for both aerospace and automotive applications within EFFIPRO; an EC granted project. The aim of the project is to develop a new energy efficient sintering process for cutting tools production. This new method is based in Joule effect sintering process which allows extremely fast sintering cycles. This work presents the preliminary results obtained during the characterisation of materials obtained using different sintering processes. A comparison of samples obtained by Spark Plasma Sintering (SPS) and Electrical resistance Sintering (ERS) is reported. It was also found that the sintering conditions for ERS are strongly influenced by the electrical conductivity of the powders. Samples obtained by SPS and ERS show a microstructure and properties similar to commercial materials.Item Structural and magnetic properties of sintered Sr-ferrites fabricated by powder injection molding(1999-08) Murillo, N.; González, J.; Guraya, C.; Gutiérrez, M.; Seco, F. J.; EXTREMAT; Tecnalia Research & InnovationStudies of micro structure (SEM and metalographic micrographs) and magnetic properties (remanent magnetisation and coercive field) have been performed on bipolar sintered Sr-ferrite permanent magnets obtained by powder injection molding (PIM) method under applied magnetic field in order to align the magnetic particles during the PIM process. Magnetic measurements on the samples were made in the parallel and perpendicular direction of the aligning magnetic field. The remanence in the direction of alignment increased sharply with the alignment field to a maximum value of 3840 Gs while the coercivity decreases to a minimum value of 3220 Oe.Item Test of a turbo-pump fed miniature rocket engine(American Institute of Aeronautics and Astronautics Inc., 2006) Scharlemann, C.; Schiebl, M.; Marhold, K.; Tajmar, M.; Miotti, P.; Guraya, C.; Seco, F.; Kappenstein, C.; Batonneau, Y.; Brahmi, R.; Lang, M.; EXTREMAT; Tecnalia Research & InnovationThe increasing application of microsatellites (from 10 kg up to 100 kg) for a rising number of various missions requires the development of suitable propulsion systems. Microsatellites have special requirements for a propulsion system such as small mass, reduced volume, und very stringent electrical power constraints. Existing propulsion systems often can not satisfy these requirements. The present paper discusses the development and test of a bipropellant thruster complying with these requirements. The main development goal of this effort was the utilization of ethanol in combination with hydrogen peroxide (H2O2) as a non-toxic propellant combination. The Turbo-Pump Fed Miniature Rocket Engine (TPF-MRE) is a bipropellant thruster consisting of four subsystems: the propellant pumps, a decomposition chamber with a monolithic catalyst, a turbine, and the thruster itself. The turbine is driven by the decomposed hydrogen peroxide and magnetically coupled with a power generator. The power produced is then used to generate a pressure head in order to deliver the propellant into the combustion chamber. This system therefore constitutes a self-sustaining system and does not rely on the limited power supply of a micro-satellite. Previous test have shown that although the thruster can be operated with ethanol and oxygen, it was not possible to ignite the thruster when utilizing hydrogen peroxide in a 70% concentration by weight. A minor redesign of the thruster and the test facility was therefore initiated. This redesign together with the use of hydrogen peroxide in higher concentration was speculated to improve this behavior. However, even though the monolithic catalysts were able to decompose hydrogen peroxide in a concentration of 87.5% with nearly 100% efficiency, it was not possible to ignite or operate the thruster. Subsequently, a thorough investigation of the baseline design and operational conditions of the thruster was conduced. It was found that the failure of the thruster to ignite is due to a combination of reasons. The combustion chamber length is too short to facilitate sufficient mixing of the propellants, making an ignition impossible or very difficult at least. Additionally, the combustion chamber pressure which was chosen such that it accommodates the performance of commercially available mircopumps is considered too low. This further deteriorates the conditions for which an ignition is feasible.Item Turbo pump FED micro-rocket engine(2004) Miotti, P.; Tajmar, M.; Seco, F.; Guraya, C.; Perennes, F.; Soldati, A.; Lang, M.; Tecnalia Research & Innovation; EXTREMATMicro-satellites (from 10kg up to 100kg) have mass, volume, and electrical power constraints due to their low dimensions. These limitations lead to the lack in currently available active orbit control systems in micro-satellites. Therefore, a micro-propulsion system with a high thrust to mass ratio is required to increase the potential functionality of small satellites. Mechatronic is presently working on a liquid bipropellant micro-rocket engine under contract with ESA (Contract No.16914/NL/Sfe - Micro-turbo-machinery Based Bipropellant System Using MNT). The advances in Mechatronic's project are to realise a micro-rocket engine with propellants pressurised by micro-pumps. The energy for driving the pumps would be extracted from a micro-turbine. Cooling channels around the nozzle would be also used in order to maintain the wall material below its maximum operating temperature. A mass budget comparison with more traditional pressure-fed micro-rockets shows a real benefit from this system in terms of mass reduction. In the paper, an overview of the project status in Mechatronic is presented.Item Turbo-pump fed miniature rocket engine(2005) Scharlemann, C.; Marhold, K.; Tajmar, M.; Miotti, P.; Guraya, C.; Seco, F.; Soldati, A.; Campolo, M.; Perennes, F.; Marmiroli, B.; Brahmi, R.; Kappenstein, C.; Lang, M.; EXTREMAT; Tecnalia Research & InnovationThe increasing application of micro-satellites (from 10kg up to 100kg) for a rising number of various missions, demands the development of new propulsion systems. Microsatellites have special requirements for a propulsion system such as small mass, reduced volume, and very stringent electrical power constraints. Existing propulsion systems often can not satisfy these requirements. Recently the development of a bipropellant thruster complying with these requirements was initiated. The main development goal of this effort was the utilization of ethanol in combination with hydrogen peroxide (H2O2) as a non-toxic propellant combination. The bipropellant thruster consists of four subcomponents: the propellant pumps, a decomposition chamber (catalyst), a turbine, and the thrusters itself. The turbine is driven by the decomposed hydrogen peroxide and coupled with a power generator. The produced power is then used to generate a pressure head in order to deliver the propellant into the combustion chamber. This system therefore constitutes a self-sustaining system and does not rely on the limited power supply of a micro-satellite. All the components were individually tested and the results are presented here. The micro-gear pump successfully delivered the required mass flow rate with the necessary pressure. The turbine was tested with a cold air flow and has not yet reached the designed power output. A redesign of the turbine is ongoing. The decomposition chamber was tested and it was verified that the H 2O2 decomposes nearly to 100%. The thruster was successfully ignited and operated for more than 45 minutes. The measured thruster wall temperatures indicate a highly efficient combustion when only ethanol and oxygen are present in the combustion chamber. The injection of water however, tends to produce flame outs. A redesign of the propellant feed system is ongoing and expected to improve the thruster operation.