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Fernandes, Joana Gonçalves - One of the best experts on this subject based on the ideXlab platform.
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Development and optimization of a Low Temperature Co-fired Ceramic suspension for Mask-Image-Projection-based Stereolithography
'Edicions de la Universitat de Barcelona', 2019Co-Authors: Fernandes, Joana GonçalvesAbstract:[eng] This dissertation has the main goal of developing ceramic materials for Mask-Image- Projection-based Stereolithography (MIP-SLA) technology, focused on electronic applications. To accomplish this aim, a low temperature co-fired ceramic (LTCC) material was selected, mainly used for radio frequency applications. Moreover, the proof of concept of AM technology hybridization and multi-materials printing is also demonstrated, opening the door to new researchers in the field of 3D-2D printing electronic devices, from both the material and technology perspectives. To successfully achieve the main goal, the different steps of the whole process were successfully achieved, i.e, formulation of a LTCC photocurable suspension, its printability by MIP-SLA technology, and the post-thermal treatment of debinding and sintering. The photocurable LTCC suspension consists of ceramic Particles dispersed in a suitable photocurable resin, which must polymerize in the visible light range, trapping the ceramic Particles. The challenge of the development and optimization of a LTCC photocurable suspension for MIP-SLA with the appropriate rheological and photocurable behavior is accomplished in this work. The printed piece contains the Polymeric Part, which must be removed (debinding) and then sintered for the densification of the final ceramic piece. This is the most difficult and time- consuming step of the whole process. The so-called debinding is one of the most challenging steps of the SLA-based technology of ceramic materials. In this sense, a detailed study of the debinding process is carried out for a deeper understanding of the degradation of the resin during the thermal debinding. For this to happen, the optimization of the temperature rate and used atmosphere during the thermal treatment is also presented in this work. In fact, the analysis and understanding of thermal treatment parameters and their repercussion on the final results is the key to successfully achieving the main goal, which is to obtain final ceramic pieces without defects. The limits of the MIP-SLA printing process are presented, analyzing the resolution, fidelity of pattern transfer, and accuracy of the printing process using the optimized LTCC suspension. The involved phenomena during the photopolymerization such as light scattering, non- uniformities of the light projection along the building platform and shrinkage during the polymerization, are analyzed and optimized for a fruitful printing process. The greatest achievement of this work is the possibility of printing complex geometry with high resolution with a LTCC material, which has never been demonstrated before in the field of additive manufacturing. This is the beginning of new breakthroughs in multimaterial printing for electronic applications.[spa] El objetivo principal de la tesis doctoral es el desarrollo y optimización de una suspensión cerámica fotocurable para la fabricación aditiva mediante la tecnología Mask-Image- Projection-Based Stereolithography (MIP-SLA), y la obtención de piezas cerámicas finales. Durante el proceso de impresión, el fotopolímero reacciona con la luz proyectada atrapando las Partículas cerámicas en su matriz, lo cual posibilita la impresión de piezas cerámicas en verde (matriz polimérica y Partículas cerámicas). Después del proceso de impresión es necesario eliminar la Parte orgánica y realizar la sinterización de la pieza para la obtención de la pieza cerámica final. El material cerámico seleccionado para la formulación de la suspensión fotocurables ha sido un cerámico de baja temperatura de co-sinterización (Low Temperature Co-fired Ceramics, LTCC), para aplicaciones electrónicas. Para el desarrollo de la suspensión fotocurable de LTCC se ha teniendo en cuenta su comportamiento reológico y sus propiedades de fotopolimerización adecuadas a la tecnología de impresión. Una vez optimizada la suspensión cerámica, se han analizado el proceso de impresión y se ha optimizado el ciclo térmico, tanto de la etapa de quemado del polímero (debinding) como del proceso de sinterización para la densificación de la pieza cerámica final. Se ha logrado una formulación adecuada a la tecnología, la cual ha permitido la impresión de piezas en verde y posterior debinding y sinterizado de las piezas con geometrías complejas. Se demuestra también la posibilidad de impresión de piezas cerámicas con circuitos impresos de plata, lo cual abre camino para el desarrollo de la impresión híbrida de multimateriales
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Development and optimization of a Low Temperature Co-fired Ceramic suspension for Mask-Image-Projection-based Stereolithography
'Edicions de la Universitat de Barcelona', 2019Co-Authors: Fernandes, Joana GonçalvesAbstract:This dissertation has the main goal of developing ceramic materials for Mask-Image- Projection-based Stereolithography (MIP-SLA) technology, focused on electronic applications. To accomplish this aim, a low temperature co-fired ceramic (LTCC) material was selected, mainly used for radio frequency applications. Moreover, the proof of concept of AM technology hybridization and multi-materials printing is also demonstrated, opening the door to new researchers in the field of 3D-2D printing electronic devices, from both the material and technology perspectives. To successfully achieve the main goal, the different steps of the whole process were successfully achieved, i.e, formulation of a LTCC photocurable suspension, its printability by MIP-SLA technology, and the post-thermal treatment of debinding and sintering. The photocurable LTCC suspension consists of ceramic Particles dispersed in a suitable photocurable resin, which must polymerize in the visible light range, trapping the ceramic Particles. The challenge of the development and optimization of a LTCC photocurable suspension for MIP-SLA with the appropriate rheological and photocurable behavior is accomplished in this work. The printed piece contains the Polymeric Part, which must be removed (debinding) and then sintered for the densification of the final ceramic piece. This is the most difficult and time- consuming step of the whole process. The so-called debinding is one of the most challenging steps of the SLA-based technology of ceramic materials. In this sense, a detailed study of the debinding process is carried out for a deeper understanding of the degradation of the resin during the thermal debinding. For this to happen, the optimization of the temperature rate and used atmosphere during the thermal treatment is also presented in this work. In fact, the analysis and understanding of thermal treatment parameters and their repercussion on the final results is the key to successfully achieving the main goal, which is to obtain final ceramic pieces without defects. The limits of the MIP-SLA printing process are presented, analyzing the resolution, fidelity of pattern transfer, and accuracy of the printing process using the optimized LTCC suspension. The involved phenomena during the photopolymerization such as light scattering, non- uniformities of the light projection along the building platform and shrinkage during the polymerization, are analyzed and optimized for a fruitful printing process. The greatest achievement of this work is the possibility of printing complex geometry with high resolution with a LTCC material, which has never been demonstrated before in the field of additive manufacturing. This is the beginning of new breakthroughs in multimaterial printing for electronic applications.El objetivo principal de la tesis doctoral es el desarrollo y optimización de una suspensión cerámica fotocurable para la fabricación aditiva mediante la tecnología Mask-Image- Projection-Based Stereolithography (MIP-SLA), y la obtención de piezas cerámicas finales. Durante el proceso de impresión, el fotopolímero reacciona con la luz proyectada atrapando las Partículas cerámicas en su matriz, lo cual posibilita la impresión de piezas cerámicas en verde (matriz polimérica y Partículas cerámicas). Después del proceso de impresión es necesario eliminar la Parte orgánica y realizar la sinterización de la pieza para la obtención de la pieza cerámica final. El material cerámico seleccionado para la formulación de la suspensión fotocurables ha sido un cerámico de baja temperatura de co-sinterización (Low Temperature Co-fired Ceramics, LTCC), para aplicaciones electrónicas. Para el desarrollo de la suspensión fotocurable de LTCC se ha teniendo en cuenta su comportamiento reológico y sus propiedades de fotopolimerización adecuadas a la tecnología de impresión. Una vez optimizada la suspensión cerámica, se han analizado el proceso de impresión y se ha optimizado el ciclo térmico, tanto de la etapa de quemado del polímero (debinding) como del proceso de sinterización para la densificación de la pieza cerámica final. Se ha logrado una formulación adecuada a la tecnología, la cual ha permitido la impresión de piezas en verde y posterior debinding y sinterizado de las piezas con geometrías complejas. Se demuestra también la posibilidad de impresión de piezas cerámicas con circuitos impresos de plata, lo cual abre camino para el desarrollo de la impresión híbrida de multimateriales
Jianzhong Fu - One of the best experts on this subject based on the ideXlab platform.
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non destructive measurement of three dimensional Polymeric Parts by magneto archimedes levitation
Polymer Testing, 2018Co-Authors: Peng Zhao, Chengqian Zhang, Jianzhong FuAbstract:Abstract In a magneto-Archimedes levitation device, a three-dimensional (3D) Polymeric Part can be levitated with a posture that is closely related to its shape and internal defects. Here, a novel non-destructive measurement method for 3D Polymeric Parts via magneto-Archimedes levitation is proposed. FLUENT-EDEM multiphase software was adopted to simulate the levitation process. From the EDEM software results, curves of levitation height, equilibrium posture and potential energy versus simulation time were obtained. The final levitation height and equilibrium posture of the Polymeric Part were determined by the principle of minimum potential energy. Several experiments with various Polymeric Parts, materials, paramagnetic media and different internal defects were carried out to verify the proposed method. Experimental results showed that the proposed method has high accuracy in measuring equilibrium posture and levitation height. For defective Parts with small voids (2 mm3), the maximum deviation between the calculated tilt angles and experimental results was less than 4.7°. In general, the proposed method has prospects of broad application in shapes and defects testing for 3D Polymeric Parts.
Peng Zhao - One of the best experts on this subject based on the ideXlab platform.
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non destructive measurement of three dimensional Polymeric Parts by magneto archimedes levitation
Polymer Testing, 2018Co-Authors: Peng Zhao, Chengqian Zhang, Jianzhong FuAbstract:Abstract In a magneto-Archimedes levitation device, a three-dimensional (3D) Polymeric Part can be levitated with a posture that is closely related to its shape and internal defects. Here, a novel non-destructive measurement method for 3D Polymeric Parts via magneto-Archimedes levitation is proposed. FLUENT-EDEM multiphase software was adopted to simulate the levitation process. From the EDEM software results, curves of levitation height, equilibrium posture and potential energy versus simulation time were obtained. The final levitation height and equilibrium posture of the Polymeric Part were determined by the principle of minimum potential energy. Several experiments with various Polymeric Parts, materials, paramagnetic media and different internal defects were carried out to verify the proposed method. Experimental results showed that the proposed method has high accuracy in measuring equilibrium posture and levitation height. For defective Parts with small voids (2 mm3), the maximum deviation between the calculated tilt angles and experimental results was less than 4.7°. In general, the proposed method has prospects of broad application in shapes and defects testing for 3D Polymeric Parts.
Chengqian Zhang - One of the best experts on this subject based on the ideXlab platform.
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non destructive measurement of three dimensional Polymeric Parts by magneto archimedes levitation
Polymer Testing, 2018Co-Authors: Peng Zhao, Chengqian Zhang, Jianzhong FuAbstract:Abstract In a magneto-Archimedes levitation device, a three-dimensional (3D) Polymeric Part can be levitated with a posture that is closely related to its shape and internal defects. Here, a novel non-destructive measurement method for 3D Polymeric Parts via magneto-Archimedes levitation is proposed. FLUENT-EDEM multiphase software was adopted to simulate the levitation process. From the EDEM software results, curves of levitation height, equilibrium posture and potential energy versus simulation time were obtained. The final levitation height and equilibrium posture of the Polymeric Part were determined by the principle of minimum potential energy. Several experiments with various Polymeric Parts, materials, paramagnetic media and different internal defects were carried out to verify the proposed method. Experimental results showed that the proposed method has high accuracy in measuring equilibrium posture and levitation height. For defective Parts with small voids (2 mm3), the maximum deviation between the calculated tilt angles and experimental results was less than 4.7°. In general, the proposed method has prospects of broad application in shapes and defects testing for 3D Polymeric Parts.
D W Noid - One of the best experts on this subject based on the ideXlab platform.
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computational simulation and modeling of polymer composite nanoParticles new insights and directions for advanced materials
Materials Today, 1999Co-Authors: Bobby G Sumpter, Kazuhiko Fukui, Michael D Barnes, D W NoidAbstract:With the recent advent o f an experimenta l t e chn ique for p roduc ing polym e r Part icles of arbitrary compos i t i on and size [1,2], compu ta t i ona l techn iques that allowdetai led examina t ion of the s t ructure and proper t i es of submic ron sized Part icles have b e c o m e invaluable tools. In Particular, molecular mode l ing provides a way of visualizing p rocesses at a sub-macromolecular level that also connec t s theory and e x p e r i m e n t . Par t icular ly a t t rac t ive f rom a computa t iona l po in t of view, is that the Part icles are ve ry close to the size scale w h e r e a c o m p l e t e atomist ic mode l can be s tudied wi thou t using artificial constraints such as per iod ic bounda ry condi t ions , yet these Particles are too small for traditional experimental s t ruc tu re /p rope r ty determination. Polymeric Part icles in the nanoand m i c r o m e t e r size range may s h o w many n e w and interest ing p roper t i es due to size reduc t ion to the point w h e r e critical length scales of physical p h e n o m e n a b e c o m e comparab le to or larger than the size of the s t ructure itself. This size-scale media t ion of the p roper t i es (mechanical , physical, electrical, c tc) opens a facile avenue for the p r o d u c t i o n of mater ia l s w i t h pred e s i g n e d p rope r t i e s . [3 ,4 ] We have d e v e l o p e d a n u m b e r of novel and p o w e r f u l c o m p u t a t i o n a l t e c h n i q u e s that a l low us to deve lop a molecu la r level unders tand ing of h o w the various proper t ies arc in f luenced bv the sizescale of the material . [5-7]The pr imary tool is a mo lecu la r dynamics-based computa t iona l a lgor i thm for generating and mode l ing po lymer nano-Particles w h i c h leads to Part icles that are as similar as possible to the exper imentally c rea ted po lymer Particles.[']