Academic literature on the topic 'Gf30'
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Journal articles on the topic "Gf30"
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Arifin, Mohd Khairol A., Nik Mohd Idham Nik Hassan, and Mohd Firdaus Abdullah. "Analysis of MPV Dashboard Using SolidWorks and ABAQUS." Key Engineering Materials 471-472 (February 2011): 634–39. http://dx.doi.org/10.4028/www.scientific.net/kem.471-472.634.
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The study is intended to measure the reliability of MPV dashboard to endure interior impact by using finite element analysis (FEA) method. A model which represents MPV dashboard was made using Solidworks and the impact simulation was done using ABAQUS. Current material being used for dashboard is ABS-GF40 and this material was proven to be reliable to withstand interior impact through the simulation that has been done in this study. Besides, this study also serve the purpose to reduce manufacturing cost using alternative materials with no less reliability compared to ABS-GF40. Similar simulation routines were applied for ABS copolymer, PP copolymer, and PVC copolymer. The simulation results showed that ABS-CF40 performance is similar to ABS-GF40, whereas the PP-CF10, PP-GF10, and PVC-GF30 exhibit almost identical behavior under impact loading. Cost assessment was carried out for all materials to assist in selecting alternative material for replacement of ABS-GF40. Hence, it was found that PP-GF10 can be used as an alternative material with cost reduction up to RM33.17 on each dashboard.
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Guamán Rivera, Santiago Alexander, Angela Edith Guerrero-Pincay, Nelson Rene Ortiz-Naveda, and Raúl Lorenzo González-Marcillo. "Prediction of the nutritional values by INRA (2018) feed evaluation system of Megathyrsus maximus subjected to different grazing strategies." Journal of Agriculture and Environment for International Development (JAEID) 117, no. 1 (June 29, 2023): 117–40. http://dx.doi.org/10.36253/jaeid-14203.
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Grazing management is a key element to optimize growth cycle of forages, which are enhanced in their chemical composition leading to the reception of greater nutritive values for feeding ruminants. Several studies have showed that the accuracy and precision of the feeding values are critical to achieve this goal, unfortunately, in Ecuador there are not referential data, despite of Megathyrsus maximus is the most forage used by livestock farmers. The predominant aim of the current study was to approach and estimate the feeding values by INRA feed evaluation system of Tanzania grass (Megathyrsus maximus) subjected at different grazing strategies. The statistical design was a randomized complete block, with a 3 × 2 factorial arrangement. Where the treatments were combinations of three grazing frequencies (GF) (30 d; termed GF30, 45 d, GF45 and 60 d, GF60) and two cutting heights (CHs; 30 and 45 cm). The agronomic data did not vary by season effect (P = 0.24 to 0.82), but GF60 had higher plant heigh and dry matter (DM) contents (P < 0.001) than other GF, although with less tiller populations (241 vs. 304 tiller/m2). By CHs effect, Tanzania grass at 30 cm had a greater DM content than 45 cm of CHs (5565 vs. 4221 ± 603 kg/ha-1; P = 0.073). All chemical determinations were affected by GF, CHs and their interaction (P < 0.001 to 0.004) with the exception on ADF between CHs (P = 0.50). Whereas only the CP and ADF values were conditioned by season effect (P = 0.001 to 0.011). Subsequently, Tanzania grass subjected at moderate rest periods and low defoliation intensities showed greater energy and proteins values than traditionally used GF60. Based in these findings, the defoliation frequency had influence on agronomic and chemical characteristics, whilst the feeding values was mainly affected by grazing intensities and weather conditions. So, the best combination regarding nutritive values should be at GF30 and GF45 combined with 45 cm of CHs.
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Domingo, Rosario, Beatriz de Agustina, and Jorge Ayllón. "Study of Drilled Holes after a Cryogenic Machining in Glass Fiber-Reinforced Composites." Applied Sciences 12, no. 20 (October 12, 2022): 10275. http://dx.doi.org/10.3390/app122010275.
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Glass fiber-reinforced composites are widely used in industry, with machining operations frequently performed, drilling, in particular, for later assembly. Although there is a smaller increase in temperature during drilling in composites than in metals, further cooling of the tool can produce improvements in some variables, such as thrust force, diameter, or surface roughness. This has been seen in studies where lower temperatures were achieved by cooling compressed air, reaching around −20 °C in plates of polyether-ether-ketone and polyamide, reinforced with glass fiber at 30% (PEEK-GF30 and PA-GF30, respectively). This paper analyzes the results of cryogenic drilling in plates of PEEK-GF30 and PA-GF30, specifically assessing thrust forces, diameter, and average surface roughness. The experimental methodology was carried out by monitoring thrust forces during cryogenic drilling using a piezoelectric dynamometer, measuring diameters with a coordinate measurement machine, and assessing surface quality with a roughness profilometer. During the cutting, the temperature of the cutting tool achieved a temperature near −120 °C from cooling with liquid nitrogen. Conducting an analytical and statistical study allowed us to determine the relationships between the measured variables and cutting conditions. Our results showed that cooling the tool during the drilling processes improved results of the cutting process.
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Wang, Haipeng, Yang Chen, Zaoyang Guo, and Yingchun Guan. "Porosity Elimination in Modified Direct Laser Joining of Ti6Al4V and Thermoplastics Composites." Applied Sciences 9, no. 3 (January 26, 2019): 411. http://dx.doi.org/10.3390/app9030411.
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Hybrid lightweight components with strong and reliable bonding qualities are necessary for practical applications including in the automotive and aerospace industries. The direct laser joining method has been used to produce hybrid joints of Ti6Al4V and glass fiber reinforced polyamide (PA66-GF30). Prior to the laser joining process, a surface texturing treatment is carried out on Ti6Al4V to improve joint strength through the formation of interlock structures between Ti6Al4V and PA66-GF30. In order to reduce the generated micro-pores in Ti6Al4V-PA66-GF30 joints, a modified laser joining method has been proposed. Results show that only very few small micro-pores are generated in the joints produced by the modified laser joining method, and the fracture strength of the joints is significantly increased from 13.8 MPa to 41.5 MPa due to the elimination of micro-pores in the joints.
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Hirsch, Patrick, Marianne John, Daniel Leipold, André Henkel, Sylvia Gipser, Ralf Schlimper, and Matthias Zscheyge. "Numerical Simulation and Experimental Validation of Hybrid Injection Molded Short and Continuous Fiber-Reinforced Thermoplastic Composites." Polymers 13, no. 21 (November 7, 2021): 3846. http://dx.doi.org/10.3390/polym13213846.
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In-situ thermoforming and overmolding of continuous fiber-reinforced thermoplastic composites by hybrid injection molding enables the mass production of thermoplastic lightweight structures with a complex geometry. In this study, the anisotropic mechanical behavior of such hybrid injection molded short and continuous fiber-reinforced thermoplastics and the numerical simulation of the resulting mechanical properties under flexural loading were investigated. For this, the influence of the volume flow rate between 25 and 100 cm3/s during injection molding of a PP/GF30 short fiber-reinforced overmolding material was studied and showed a strong effect on the fiber orientation but not on the fiber length, as investigated by computer tomography and fiber length analysis. Thus, the resulting anisotropies of the stiffness and strength as well as the strain hardening investigated by tensile testing were considered when the mechanical behavior of a hybrid test structure of short and continuous fiber-reinforced thermoplastic composites was predicted by numerical simulations. For this, a PP/GF60 and PP/GF30 hybrid injection molded test structure was investigated by a numerical workflow with implemented injection molding simulation data. In result, the prediction of the mechanical behavior of the hybrid test structure under flexural loading by numerical simulation was significantly improved, leading to a reduction of the deviation of the numerically predicted and experimentally measured flexural strength from 21% to 9% in comparison to the isotropic material model without the implementation of the injection molding data.
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Borges, Catarina S. P., Alireza Akhavan-Safar, Eduardo A. S. Marques, Ricardo J. C. Carbas, Christoph Ueffing, Philipp Weißgraeber, and Lucas F. M. da Silva. "Effect of Water Ingress on the Mechanical and Chemical Properties of Polybutylene Terephthalate Reinforced with Glass Fibers." Materials 14, no. 5 (March 7, 2021): 1261. http://dx.doi.org/10.3390/ma14051261.
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Short fiber reinforced polymers are widely used in the construction of electronic housings, where they are often exposed to harsh environmental conditions. The main purpose of this work is the in-depth study and characterization of the water uptake behavior of PBT-GF30 (polybutylene terephthalate with 30% of short glass fiber)as well as its consequent effect on the mechanical properties of the material. Further analysis was conducted to determine at which temperature range PBT-GF30 starts experiencing chemical changes. The influence of testing procedures and conditions on the evaluation of these effects was analyzed, also drawing comparisons with previous studies. The water absorption behavior was studied through gravimetric tests at 35, 70, and 130 °C. Fiber-free PBT was also studied at 35 °C for comparison purposes. The effect of water and temperature on the mechanical properties was analyzed through bulk tensile tests. The material was tested for the three temperatures in the as-supplied state (without drying or aging). Afterwards, PBT-GF30 was tested at room temperature following water immersion at the three temperatures. Chemical changes in the material were also analyzed through Fourier-transform infrared spectroscopy (FTIR). It was concluded that the water diffusion behavior is Fickian and that PBT absorbs more water than PBT-GF30 but at a slightly higher rate. However, temperature was found to have a more significant influence on the rate of water diffusion of PBT-GF30 than fiber content did. Temperature has a significant influence on the mechanical properties of the material. Humidity contributes to a slight drop in stiffness and strength, not showing a clear dependence on water uptake. This decrease in mechanical properties occurs due to the relaxation of the polymeric chain promoted by water ingress. Between 80 and 85 °C, after water immersion, the FTIR profile of the material changes, which suggests chemical changes in the PBT. The water absorption was simulated through heat transfer analogy with good results. From the developed numerical simulation, the minimum plate size to maintain the water ingress unidirectional was 30 mm, which was validated experimentally.
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Borges, Catarina S. P., Eduardo A. S. Marques, Ricardo J. C. Carbas, Alireza Akhavan-Safar, Christoph Ueffing, Philipp Weißgraeber, and Lucas F. M. da Silva. "Effect of the Interface/Interphase on the Water Ingress Properties of Joints with PBT-GF30 and Aluminum Substrates Using Silicone Adhesive." Polymers 15, no. 4 (February 4, 2023): 788. http://dx.doi.org/10.3390/polym15040788.
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The aim of this work is to analyze the difference between silicone/composite and silicone/metal interphases, both in terms of water diffusion behavior and failure of the aged joints. For that, silicone joints with two different suhbstrates were prepared. The substrates were polybutylene terephthalate with 30% of short glass fiber (PBT-GF30) and 6082-T6 aluminum. It is assumed that the water uptake of the joints is equal to the water uptake of the substrate, adhesive, and interphase. Therefore, knowing the first three, the last could be isolated. To study the water diffusion behavior of the complete joint, rectangular joints were prepared, immersed in water and their water uptake was measured. The water immersion was conducted at 70∘C. It was concluded that the aluminum/silicone joints absorbed more water through the interphase region than the PBT-GF30/silicone joints, since the difference between the expected water uptake and the experimentally measured mass gain is significantly higher, causing adhesive failure of the joint. The same was not observed in the PBT-GF30/silicone, with a more stable interphase, that does not absorb measurable quantities of water and always exhibits cohesive failure.
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Wypych, Artur, Piotr Siwak, Daniel Andrzejewski, and Jaroslaw Jakubowicz. "Titanium Plasma-Sprayed Coatings on Polymers for Hard Tissue Applications." Materials 11, no. 12 (December 13, 2018): 2536. http://dx.doi.org/10.3390/ma11122536.
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The paper presents the results of titanium plasma spraying (TPS) on polymer substrates. Polyethylene (PE300), polyamide PA6, and fiber glass-reinforced polyamide (PA6.6-GF30) were used as substrates. The PE300 and PA6.6-GF30 substrates exhibited appropriate behavior during the TPS process, whereas the PA6 substrate did not “accept” Ti during plasma spraying, and the coating did not form. The TPS coatings exhibited low porosity and high homogeneity, and they had a typical multilayer structure composed of Ti and its oxides. The nanoindentation test showed good mechanical properties of the coatings and demonstrated a hardness and a Young’s modulus of approximately 400 HV and 200 GPa, respectively. The bending test confirmed the good adhesion of the titanium coatings to the polymer substrates. The Ti coatings did not fall off the substrate after its significant bending deformation.
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Astrouski, Ilya, Tereza Kudelova, Josef Kalivoda, and Miroslav Raudensky. "Shear Strength of Adhesive Bonding of Plastics Intended for High Temperature Plastic Radiators." Processes 10, no. 5 (April 20, 2022): 806. http://dx.doi.org/10.3390/pr10050806.
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The use of adhesive joints has increased in recent decades due to their competitive features in comparison with other joining methods. They can be used in specific applications where there is no possibility to use alternative connection techniques. Adhesive bonding was used to assemble the prototype of a high-temperature car radiator (operated up to 125 °C) with a total of 12,240 plastic tubes. This work aims to estimate the shear strength of different adhesives intended for bonding the plastics used to assemble the above-mentioned high-temperature radiator. Fourteen commercial adhesives were tested with one thermoset plastic (G11 glass fabric epoxy sheets) and two glass-reinforced thermoplastics (polyamide PA66-GF30 and polyphenylene sulfide PPS-GF40). Tests were conducted according EN 1465 to determine tensile lap-shear strength of bonding. Testing showed that only 4 of the 14 adhesives tested exhibit substantial bonding strength at temperatures above 120 °C and only one is resistant at 180 °C. The AS60/AW60 adhesive showed the best results for all three substrates: 1.6 MPa for epoxy sheets and PA66-GF, and 1.4 MPa for PPS-GF40. Additionally, the influence of the surface treatment with cold plasma was evaluated on a clean and activated bonding surface, causing a 30% increase in the shear strength.
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Mata, Francisco, Pedro Reis, and J. Paulo Davim. "Physical Cutting Model of Polyamide Composites (PA66 GF30)." Materials Science Forum 514-516 (May 2006): 643–47. http://dx.doi.org/10.4028/www.scientific.net/msf.514-516.643.
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Polymeric matrix composite materials presents advantages in a great number of applications due to their high specific strength and stiffness, wear resistance, dimensional stability, low weight and directional properties. As result of these properties and potentials applications exists a strong need to understand the manufacturing processes, particularly the machining process of these composite materials. This paper presents an investigation above the modelization of the cut, turning of small workpieces, on two materials: a polymer PA 6 (Polyamide) and a composite PA 66-GF30 (reinforced with 30% of glass fiber). The tests were carried out polycrystalline diamond tools (PCD). The objective of this experimental study is to evaluate the influence of the glass fiber reinforcement on the friction angle (ρ), shear angle (Φ), normal and shear stresses (σ, τ), chip deformation (ε) under the cutting parameters prefixed (cutting velocity and feed rate). The experimental model was compared with the theoretical model of Merchant.
Dissertations / Theses on the topic "Gf30"
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Lapa, Vítor Manuel da Cruz. "Optimização da maquinagem do PEEK e seus compósitos PEEK/CF30 e PEEK/GF30." Doctoral thesis, Universidade de Aveiro, 2007. http://hdl.handle.net/10773/2557.
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Doutoramento em Engenharia MecânicaSendo o PEEK (poli-éter-éter-cetona) um termoplástico de Engenharia de última geração que apresenta excelentes propriedades físicas/mecânicas, tem a possibilidade de ser aplicado simples ou compósito nos mais variados tipos de componentes das indústrias (automóvel, aeronáutica, aeroespacial, nuclear, transportes, petrolífera, médica, biomédica, e outras). Este presente trabalho pretende mostrar a sua aptidão para ser processado através da maquinagem convencional por arranque de apara (torneamento, fresagem e furação). Verificou-se que a maquinagem do PEEK e seus compósitos PEEK/CF30 e PEEK/GF30, obrigou à utilização de ferramentas diamantadas com geometrias especiais e parâmetros de corte apropriados. Na maquinagem em corte ortogonal destes três materiais, em virtude dos diferentes tipos de apara obtidos, pôde ser aplicado o modelo de Merchant. Igualmente, utilizando o corte ortogonal, foi possível desenvolver uma Rede Neuronal Artificial (RNA) que aponta para a modelação eficiente de um conjunto de condições de maquinagem dos materiais compósitos com matriz de PEEK. A aprendizagem supervisionada da RNA baseou-se num Algoritmo Genético (AG) suportado por uma estratégia elitista. Os resultados obtidos mostram que a pesquisa evolucionária é uma boa opção, quando se associa o processo de optimização à aprendizagem supervisionada. Na maquinabilidade dos três materiais, as menores forças de corte ocorrem para o PEEK seguido do PEEK/GF30, sendo mais elevadas para o PEEK/CF30. Quanto às rugosidades nas superfícies obtidas, elas são menores para o PEEK seguidas do PEEK/CF30, enquanto que o PEEK/GF30 apresenta os valores mais elevados. Nas operações de fresagem e furação verificou-se que a utilização de ferramentas com geometrias especiais é um factor importante para se obterem forças de corte optimizadas e superfícies com bom acabamento.
Being PEEK (poli-ether-ether-ketona) a last generation engineering thermoplastic which has excellent physical/mechanical properties, it can be used both simple and composite in several varied sorts of components in automobile, aeronautical, aerospatial, nuclear, transportation, oil, medical, biomedical, and other industries. This present research intends to show its capability for being processed through conventional machining by taking off chip (turning, milling and drilling). It has been observed that the machining of PEEK and its composites PEEK/CF30 and PEEK/GF30, required the use of diamond tools with especial geometries and proper cutting parameters. For the machining in orthogonal cutting of these three types of materials, it was possible to use the Merchant model, due to the different sorts of chips acquired. Likewise, using the orthogonal cutting it was possible to develop an Artificial Neural Network (RNA) which leads to the efficient moulding of a series of machining conditions of composites materials with a PEEK matrix. The supervisioned learning RNA is based on a Genetic Algorithm (AG) supported by an elitist strategy. The results obtained show that, when the optimization process is linked to the supervisioned learning, the evolutionary research is a good option. In the machinability of these three materials, the lowest cutting forces occur for PEEK, then for PEEK/GF30, being the highest values for PEEK/CF30. In what concerns the roughness on the surfaces obtained, PEEK has the lowest values, followed by PEEK/CF30 and while PEEK/GF30 presents the highest values. By milling and drilling, it has been observed that the use of tools with special geometries is an important factor to get optimized cutting forces and a good surface finish.
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Ammar, Ahmed. "Simulation numérique du comportement et de l'endommagement d'un matériau composite à fibres courtes : application au PA6/GF30 sous conditions environnementales." Electronic Thesis or Diss., Amiens, 2021. http://www.theses.fr/2021AMIE0080.
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Les travaux menés dans le cadre de cette thèse ont pour objectif le développement d'une approche numérique performante, basée sur la Méthode des Éléments Discrets (MED) pour simuler le comportement hygro-thermo-mécanique d'un matériau composite à fibres de verre courtes. La modélisation discrète proposée est mise en œuvre dans le cas d'un matériau composite Polyamide 6 renforcé avec 30% de fibres de verre (PA6/GF30). Tout d'abord, les propriétés mécaniques ainsi que les mécanismes d'endommagement du PA6/GF30 sont évalués expérimentalement. Ensuite, un modèle 3D par Éléments Discrets(ED), en s'appuyant sur une méthodologie originale, est développé et validé par comparaison avec des approches micromécaniques et des résultats expérimentaux,en termes de propriétés élastiques. Par ailleurs, le modèle discret mis au point est exploité afin de simuler le processus de délamination en mode I, II et mixte en utilisant un modèle de zone cohésive 3D définit selon une loi de traction-séparation bilinéaire. La décohésion interfaciale fibre/matrice sous sollicitations mécaniques, respectivement dans le cas d'un composite mono-fibre et multifibre est également étudiée. Compte tenu du caractère hydrophile du PA6, l'introduction du modèle de décohésion trouve son intérêt dans la prise en compte de l'endommagement interfacial dû à l'absorption d'eau à l'interface fibre/matrice en présence d'humidité. Par conséquent, des paramètres hygro-thermo-mécaniques sont intégrés au modèle ED afin de tenir compte du gonflement hygroscopique et de l'endommagement du PA6/GF30 dans une large gamme de conditions environnementales. Des comparaisons avec la Méthode des Éléments Finis (MEF) ont été établies afin de vérifier la validité du modèle ED proposéThis thesis work aims at developing a powerful numerical tool based on the Discrete Element Method (DEM) to simulate the hygro-thermo-mechanical behaviour of a short glass fibre composite material. The proposed discrete modelling is performed in the case of a Polyamide 6 composite material reinforced with 30% of glass fibres (PA6/GF30). First of all, mechanical properties as well as damage mechanisms of PA6/GF30 are evaluated using experimental campaign. Then, a 3D Discrete Element (DE) model based on an original methodology is developed and validated by comparison with micromechanical approaches and experimental results in terms of elastic behaviour of PA6/GF30. Furthermore, the developed discrete model is exploited to simulate delamination process on mode I, II and mixed mode using a 3D cohesive zone model with a bilinear tractionseparation law. The fibre/matrix interfacial decohesion under mechanical stress,respectively in the case of a single-fibre and multi-fibre composite is also studied. Given the hydrophilic nature of PA6, the introduction of the decohesion model is interesting in order to take into account the interfacial damage due to water absorption at the fibre/matrix interface in the presence of moisture. Therefore, hygro-thermo-mechanical parameters are integrated into the discrete model in order to take into account the hygroscopic swelling and the damage of PA6/GF30 material under a wide range of environmental conditions. Comparisons with the Finite Element Method (FEM) have been established to check out the validity of the proposed DE model
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Chekkour, Rabii. "Etude des mécanismes d'endommagement dans un polyamide 66 renforcé par des fibres de verre courtes, soumis à l'effet de vieillissement de l'éthylène glycol et de l'antigel." Electronic Thesis or Diss., Paris, HESAM, 2023. http://www.theses.fr/2023HESAE006.
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Le but de ce travail est d'étudier l'effet du vieillissement dans l'éthylène glycol et l'antigel sur le comportement global et les mécanismes d'endommagement du polyamide 66 (PA66) et du polyamide 66 renforcé par des fibres de verre courtes (PA66/GF). À cette fin, un dispositif expérimental de vieillissement adéquat est conçu et présenté pour conditionner les échantillons dans le glycol et l'antigel à différentes durées de vieillissement. L'effet d'absorption du milieu de vieillissement est analysé par le gonflement et la variation de masse (absorption). L'effet du refroidissement est également étudié en appliquant deux méthodes de refroidissement. Des essais de traction monotones sont effectués pour étudier l'effet du vieillissement sur le PA66 et le PA66/GF. Une investigation MEB (Microscope Electronique à Balayage) est ensuite réalisée pour caractériser les mécanismes d'endommagement et leur évolution en fonction de la durée de vieillissement. Des observations par tomographie à rayons X (µCT) sont également réalisées pour quantifier les dommages en fonction de la durée du vieillissement, du matériau et de la zone d'intérêt (AOI).Les résultats expérimentaux montrent que l'absorption de glycol et de l'antigel est plus importante pour la matrice PA66 non renforcée que pour le composite PA66 renforcé par des fibres de verre courtes. De plus, la rigidité, ainsi que la déformabilité du matériau, sont considérablement affectées par le vieillissement. En termes de dégradation du composite, les principaux mécanismes d'endommagement sont situés à l'extrémité de la fibre et à l'interface fibre-matrice, et pour les durées de vieillissement élevées, la cavitation dans la matrice polymère est constatée. L'étude par microtomographie à rayons X a indiqué que l'endommagement est principalement localisé au cœur et à la surface des échantillons, ce qui est dû à la microstructure cœur-peau bien connue des composites PA66/GF injectés. Toutes ces conclusions permettent de déduire l'effet significatif et irréversible du vieillissement du glycol et de l'antigel sur le comportement mécanique global et les mécanismes d'endommagement des matériaux étudiésThe aim of this work is to study the effect of ethylene glycol and coolant aging on the overall behavior and the damage mechanisms of the Polyamide 66 (PA66) and the short glass fiber reinforced polyamide 66 (PA66/GF). To this end, a proper experimental aging setup is designed and presented for conditioning the samples in glycol and coolant at different aging durations. The aging media absorption effect is analyzed through the swelling and the mass variation (uptake). The effect of cooling is also studied by applying two cooling methods. Moreover, monotonic tensile tests are performed to study the aging effect on the PA66 and PA66/GF. SEM (Scanning Electron Microscopy) investigation is then performed to characterize the damage mechanisms and their evolution with the increase of the aging duration. X-ray micro-computed tomography (µCT) observations are also carried out to quantify the damage depending on the aging duration, the material, and the area of interest (AOI).Experimental findings show that the glycol and coolant absorption is more important for the PA66 unreinforced matrix than for the short glass fiber-reinforced PA66 composite. In addition, the stiffness, as well as the material deformability, are found to be significantly affected by aging. In terms of composite degradation, the main damage mechanisms are the damage at the fiber's end and the fiber-matrix interface, and for the high aging durations, cavitation in the polymer matrix is observed. The X-ray µCT investigation has indicated pronounced damage mostly located at the core and surface of the samples, which is due to the well-known shell-core microstructure of injected PA66/GF composites. All these conclusions lead to inferring the significant and irreversible effect of glycol and coolant aging on the bulk mechanical behavior and damage mechanisms of the investigated materials
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Raffai, Peter. "Vytvoření a validace výpočtového FEM modelu kliky dveří pro crashové výpočty." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2012. http://www.nusl.cz/ntk/nusl-230249.
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The aim of this master’s thesis was to create a component model of a door handle stiffener used by the Volkswagen concern, which can be used for crash computations. Also to tune its parameters the way, its behavior corresponds the most to the real part’s. In the theoretical part the current regulations of the Euro NCAP are presented, concerning the testing and evaluation of the passive safety of new vehicles. Attention is focused on the evaluation of the side impact barrier tests, where the effect of the door handle stiffener’s damage is reflected the most. Shown are the reasons for the effort to simulate the real behavior of the stiffener, the factors, which initialized the born of the studied problem. The practical part starts with the creation of the FEM mesh of the part based on its 3D CAD model, also describes the requirements for the mesh quality, as well as the used tools and methods. Further on investigated are the characters of real damages of the door handle area during side impacts, based on which the component tests are proposed for the validation of the simulation model. Experimental research consists of the stiffener’s testing for simple bend and twist loads, three specimens each. After the execution of the tests the results get compared with the corresponding simulations. Modifications are made on the model according to the acquired results: refinement of the FEM mesh, new material model usage with failure for shell elements and definition of real material characteristics for the used thermoplastics. The latest obtained simulation dependencies are compared with the measured values again, the results are evaluated at last.
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Corredori, Paulo César 1966. "Aplicação de polipropileno com 35% de fibra de vidro (PP GF35) em substituição à poliamida com 35% de fibra de vidro (PA6 GF35) na fabricação de coletores de admissão em motores de 03 cilindros Bi-combustível." [s.n.], 2015. http://repositorio.unicamp.br/jspui/handle/REPOSIP/265770.
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Orientador: Cecilia Amélia de Carvalho ZavagliaDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecânica
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Resumo: Este mundo que vivemos está se tornando extremamente competitivo dia após dia, a apenas cinquenta anos, os motores ciclo Otto permaneciam quase os mesmos quando foram inventados pelo engenheiro alemão Nikolaus August Otto no final do século 19. Foi somente no final da década de 1970 que os antigos motores começaram a ganhar apelos tecnológicos, como injeção eletrônica, ignição eletrônica, controle de emissões e gás carbônico, etc., com isso, todas as montadoras começaram a buscar soluções que fizessem do seu veículo, o melhor ou o mais econômico e menos poluente. Face às novas exigências governamentais ao redor do mundo, todas as montadoras e autopeças estão trabalhando incansavelmente na busca de várias soluções, soluções estas que vão desde a diminuição de emissões evaporativas, redução do consumo de combustível, seja em função de um motor mais econômico quanto a melhorias de aerodinâmica, que resulta em menor fenômeno de arraste e consequente economia de combustível. Sabe-se também que redução de peso impacta diretamente na redução do fenômeno de arraste, portanto, gera um menor consumo de combustível, por isso, estamos vendo o crescente interesse das indústrias automotivas em substituir as antigas e atuais peças em metal que são normalmente pesadas, para peças extremamente mais leves em plásticos de engenharia e com alta resistência térmica, mecânica, etc., e quem nem por isso não mantenham a mesma qualidade funcional das peças em metal. Plásticos de engenharia como a Poliamida 6 com 35% de fibra de vidro (PA6 GF35), já estão sendo aplicados no mercado automotivo a pelo menos quase 20 anos, pois os primeiros coletores de admissão e filtro de ar em plástico nasceram utilizando esta matéria prima, hoje em dia, nesta busca por redução de peso e consequentemente preço, um material plástico chamado Polipropileno com 35% de fibra de vidro (PP GF35), que até não muito tempo atrás era de segunda linha, passa a ser de suma importância para alcançar objetivos que técnicos e monetários que até outro dia, somente era possível com a Poliamida 6 com 35% de fibra de vidro (PA6 GF35). Hoje em dia o polipropileno é um polímero de destaque no setor automotivo, pois ele se destaca pela alta resistência química e solvente, boa estabilidade dimensional, flexibilidade, durabilidade, excelente balanço entre impacto e rigidez. Sendo assim, uma matéria prima que era utilizada na fabricação de fios de tecelagem, embalagens flexíveis, brinquedos, copos plásticos, corpo de eletrodomésticos, está sendo usado em peças de alto valor agregado, alto e com tal desempenho técnico como um coletor de admissão e em quase todas as peças de acabamento interno e externo da maioria das empresas automotiva do Brasil e do mundo
Abstract: Due to strong competition among automotive companies around the world, and also by the incessant search in order to reduce weights in vehicles, reducing fuel consumption and therefore reduce carbonic gas emissions, the automakers are working on several fronts in order to reach the targets already defined through the government¿s laws. Given these several requests, the automotive parts industries, together with the raw materials industry, are working to achieve these goals. Thus, reductions in power cell consequently the numbers of cylinders in the engines are already a reality, for example three cylinders engines are replacing the four cylinder engines, and the most important comment, and they are keeping the same driving force. In addition, we are working so hard in order to replace the current Intake Manifold in Polyamide 6 with 35% glass fiber (PA6 GF35), for Polypropylene with 35% glass fiber (PP GF35), so is being reduced around 15% of weight, changing only the raw material. Polypropylene (PP), who was a second-line raw material in the past at the automotive world, becomes to move of other excellent quality of baseline of importance, as well, as reducing the weight of the piece, how it reduces the price piece value, as also the polypropylene is cheaper around of 15% more than the polyamide 6. This new polypropylene for Intake Manifold needs to be heat stabilizer, but needs not to be flame retardant. Many characteristics had been considered very important in the decision matrix in order to reach a good polymer, as well, mechanical resistance to the tensile and impact, density, water absorption, thermal resistance, chemical resistance regarding fuel, injection process and the availability of mass production. Only twenty years ago, all engines Cycle Otto were manufactured, using Intake Manifold in aluminum material, due to the aluminum caused a chemical reaction in physical contact with the alcohol, it was invented the Intake Manifold in Polyamide 6. Today all the automotive world uses Intake Manifold in Polyamide 6 for Cycle Otto application, but due to the excellent results using the polypropylene raw material, all automakers are moving to this new raw material, which in a not so distant past, was regarded as the second line in the automotive industry
Mestrado
Materiais e Processos de Fabricação
Mestre em Engenharia Mecânica
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Bourgogne, Quentin. "Contribution à l’étude du comportement mécanique d’un PPS/GF40 sous différents chargements avec prise en compte des effets de l’environnement de sollicitation : étude expérimentale et modélisation multi-échelle pour application au développement de pièces automobiles." Electronic Thesis or Diss., Université de Lorraine, 2020. http://www.theses.fr/2020LORR0181.
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L’immersion permanente dans le liquide de refroidissement et les fortes variations de températures inhérentes à certaines applications automobiles constituant un environnement défavorable aux composites plastiques, les effets de cet environnement sur ces matériaux doit être connus afin de permettre une conception fiable des composants. Cette thèse présente une étude expérimentale et théorique sur un PPS/GF 40 et sa matrice. Les variations de températures et le vieillissement du matériau lié à l’immersion dans le liquide de refroidissement ont été investiguées de manière expérimentale via des essais de tractions cycliques et monotones sur le plastique pur et sur le composite en faisant varier la proportion de glycol dans le liquide de refroidissement. Les résultats de ces essais ont permis l’identification des principaux phénomènes physiques à l’œuvre dans le PPS pur et responsables des évolutions de son comportement mécanique en fonction de cet environnement hydro-thermique. Ces observations expérimentales ont permis la mise en place d’un modèle phénoménologique traduisant le comportement complexe du PPS et de l’extrapoler pour différentes températures. Les effets du vieillissement ont été intégrés au sein de ce même modèle via l’établissement d’une équivalence température/immersion. A partir de l’étude réalisée sur la matrice PPS, le modèle proposé a été extrapolé au niveau du composite via une homogénéisation analytique de son comportement. Un certain écart a été observé entre la prédiction du comportement plastique et le comportement observé expérimentalement. Une investigation par éléments finis de la cohésion fibre/matrice par endommagement d’inter-phase a été menée afin d’expliquer ces différences. Ce travail a permis de mettre en exergue l’influence du vieillissement sur cette cohésion et de quantifier la perte de résistance de cette inter-phase induite par l’immersion. Enfin, une étude expérimentale en fatigue a été menée sur le composite. Les similitudes observées avec le comportement en quasi-statique ont permis de réutiliser des paramètres du modèle développé afin d’extrapoler les courbes de Wöhler pour différentes températures. Cette extrapolation étant alors possible, un modèle 1D a été développé afin d’estimer l’élévation de température induite dans le matériau suite aux phénomènes d’auto-échauffement induits par la sollicitation en fatigue, tout en prenant en considération les effets du vieillissement sur la microstructure du matériauThis thesis presents an experimental and theoretical study conducted on a PPS/GF40 and its matrix. Widely used for under-the-hood applications in the automotive industry, those materials are subjected to high temperatures and aging effects of cooling liquid. Therefore, the understanding of those phenomena is essential to design mechanical parts. Thus, an experimental campaign in the tensile mode has been carried out with different temperatures and glycol proportions in the cooling liquid, for monotonic and cyclic loadings on neat and reinforced PPS. The results of these tests allowed us to highlight some of the main physical phenomena occurring during these solicitations under tough hydro-thermal conditions. Taking into account this analysis, a visco-elasto-pseudo-viscoplastic model is proposed. Moreover, this model allows the consideration of the cooling liquid effects and its constituents by temperature/humidity equivalence. The accuracy of the model was confronted to an artificial intelligence based one, in order to study the maximal accuracy physically reachable. Finally, the evolution of the model parameters has been studied with the adjunction of short glass fibres and for specifics orientation distribution. Starting from the study of the mechanical behavior of the PPS matrix, an analytical homogenization was then performed. Differences between experimental and predicted plastic behaviors were highlighted. Finite element analyses considering inter-phase damage were done at different temperatures and for several fiber orientations so to explain differences arising between analytical approach and experimental results. This work allowed a study of the evolution of the impact of this damage on mechanical properties as a function of temperature and fiber orientation. This work led to highlight a weakening of the fiber/matrix interface for a liquid aged composite and to quantify the decrease of the interface properties. Finally, fatigue behavior of the composite is studied as a function of fiber orientation. The modeling parameters determined from the study of the monotonic behavior of the composite were taken into account to propose a prediction of the Wöhler curves as a function of temperature. The prediction of the Wöhler curves as a function of temperature being possible, a 1D model was then proposed in order to evaluate the increase of temperature due to self-heating phenomenon during fatigue loading, considering ageing consequences
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Castro, Daniel Valente. "Projeto de estrutura de base polimérica para a construção civil." Master's thesis, 2015. http://hdl.handle.net/10316/29065.
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Tese de Mestrado em Engenharia Mecânica, especialidade de Produção e Projeto, apresentada à Faculdade de Ciências e Tecnologia da Universidade de Coimbra.O presente trabalho estuda a viabilidade de uma estrutura alternativa às utilizadas na construção civil, tanto em termos dos materiais selecionados como em termos de método de construção de habitações unifamiliares. Um dos objetivos estabelecidos é a estrutura ser simples e rápida de montar, ao contrário de alguns tipos de construção já existentes, aliada a um processamento de materiais simples e de baixo custo, de modo a viabilizar a produção em série. Neste contexto, o trabalho explora a utilização de materiais poliméricos reforçados, mais concretamente de uma mistura de politereftalato de butileno com politereftalato de etileno, com a adição de 30% de fibra de vidro. O conceito adotado é baseado na construção modular e envolve componentes de dimensões pré-definidas, mais concretamente três tipos de perfis e quatro dimensões de módulos. O estudo é complementado com a análise do processo de fabrico dos componentes e respetivos custos, resultantes da produção em série de estruturas baseadas no conceito proposto. O estudo é complementado também com a análise de materiais e técnicas que podem ser combinados com a estrutura, de modo a garantir os requisitos de funcionalidade e permitir semelhança estética com a construção convencional. A utilização do programa de CAD da Dassault Systèmes, CATIA® V5 R20, permite planear toda a construção e definir de forma rigorosa a lista de componentes, o que garante a minimização dos desperdícios de material e de derrapagens nos custos.
This work studies the feasibility of an alternative structure to those used currently in construction, both in terms of the materials selected and in terms of construction method for a family house. One of the objectives is that the structure is simple and quick to assemble, unlike some types of existing construction, combined with simple processing, low cost materials, to facilitate the mass production. In this context, the work explores the use of reinforced polymeric material, more specifically a mixture of butylene terephthalate and ethylene terephthalate, with the addition of 30% glass fiber. The concept adopted is based on modular construction and involves the use of components with pre-defined dimensions, more specifically three types of profile and four modules with different dimensions. The study is completed with the analysis of the manufacturing process of the components and their respective costs, resulting from the mass production of structures based on the proposed concept. The study is also complemented with the analysis of materials and techniques that can be combined with the structure, to ensure the functionality requirements and allow aesthetics similar to conventional construction. The use the of CAD program of Dassault Systèmes CATIA® V5 R20, allows the planning of the construction, including the accurate definition of the list of components, which ensures minimization of waste material and cost overruns.
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Castagnet, S., C. Nadot-Martin, A. Bernasconi, E. Lainé, E. Conrado, and Philip D. Caton-Rose. "Through process modeling for the fatigue life assessment of notched injection-molded specimens." 2014. http://hdl.handle.net/10454/10610.
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NoThe study is based on a previously proposed methodology for multiaxial fatigue life assessment of injection-molded components (called ‘Through Process Modeling’ (TPM)). The present contribution focuses on stress concentration effects induced in notched samples. Purely macroscopic approaches are unable to capture the different mechanical responses of variably injected parts with the same shape. A high interest of the present method is to take into account the difference of fiber orientation resulting from the process. After briefly reminding the TPM method, it will be shown that good lifetime estimations are obtained for laterally injected samples, from a fatigue criterion identification based on longitudinally injected ones.
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Lama, Aelina. "Screening of fungi with potential for producing fructooligosaccharides with enhanced bioactivity." Master's thesis, 2017. http://hdl.handle.net/10198/14398.
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Fructooligosaccharides (FOS) are present in plants and fruits at low concentrations and with varying individual relative proportions. So, for the industrial application, fructooligosaccharides extraction from natural sources may not be economically viable. Recently, several works have been published within the field of research usually aiming to establish the best experimental conditions to maximizing fructooligosaccharides yields/synthesis. However, although it is known that these compounds may have a great health impact, it is also reported that beneficial health effects may depend on the relative fructoligosaccharisdes composition, seeming that nystose-rich diet is preferable compared to a kestose-rich preparation, exhibiting a higher anti-hydroxyl radical activity. So, in this work, a screening study was firstly carried out aiming to evaluate the bioactive activity of the fermentation broths obtained using different fungi (A. aculeatus, A. japonicus, P. corylophilum, P. spinulosum and P. thomii) with reported potential for producing fructooligosaccharides. Based on the screening antioxidant results (DPPH free radical scavenging activity and iron chelating activity), A. aculeatus was selected as the fungi with the highest antioxidant potential. After, batch fermentations were carried out aiming to establish, based on an experimental design, the initial sucrose concentration (from 88 to 265 g/L) and fermentation temperature (from 22 to 32ºC), which enhance the broths bioactivities. Among the two evaluated experimental conditions, the initial sucrose concentration significantly influenced biomass growth (a maximum value of 16± 1.5 g was achieved) although it did not significantly affect the maximum FOS yield obtained, which varied between 51 to 59 g of FOS/g of initial sucrose. Finally, the preliminary results obtained did not allowed establishing straightforward correlation betwwen antioxidant activities of the fermentation broths and the individual or total FOS concentrations.Fruto-oligossacáridos (FOS) podem ser encontrados em plantas e frutos, embora em concentrações reduzidas e com diferentes proporções relativas de cada FOS individual. Assim, de um ponto de vista industrial, a extração de fruto-oligossacáridosa partir de fontes naturais pode não ser economicamente viável. Recentemente, vários trabalhos foram publicados com o objetivo de estabelecer as melhores condições experimentais para maximizar os rendimentos / síntese de fruto-oligossacáridos. No entanto, embora se saiba que estes compostos podem ter um grande impacto na saúde, também tem sido reportado que os efeitos benéficos para a saúde podem depender da composição relativa de fruto-oligossacáridos. Aparentemente, uma dieta rica em nistose é preferível em comparação com uma preparação rica em questose, exibindo uma maior atividade antioxidante. Assim, neste trabalho, realizou-se um estudo inicial para avaliar a bioatividade de meios fermentativos obtidos usando diferentes fungos (A. aculeatus, A. japonicus, P. corylophilum, P. spinulosum e P. thomii), os quais são conhecidos produtores de FOS. Com base nos resultados preliminares da actividade antioxidante de (atividade de eliminação de radicais livres DPPH e atividade quelante de ferro), o fugo A. aculeatus foi selecionado como sendo aquele que apresentava maior poder antioxidante. Posteriormente, foram realizadas fermentações com o objetivo de estabelecer, com base num desenho experimental, a concentração inicial de sacarose (de 88 a 265 g / L) e a temperatura de fermentação (de 22 a 32ºC), que maximizava o poder antiooxidante dos meios fermentativos. De entre as duas condições experimentais avaliadas, verificou-se que a concentração inicial de sacarose influenciou significativamente o crescimento da biomassa (valor máximo de 16 ± 2 g), embora não tenha afetado significativamente o rendimento de FOS obtido, que variou entre 51 a 59 g de FOS/g de sacarose inicial. Finalmente, os resultados preliminares obtidos não permitiram estabelecer uma correlação direta entre as atividades antioxidantes dos caldos de fermentação e as concentrações de FOS individuais ou totais.
Book chapters on the topic "Gf30"
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Zhang, Xiaojia, Lei Den, Changyong Lin, and Bo Liu. "Research on Static Viscoelastic and Tribological Properties of PP-EPDM, PP-GF30 and ABS in Automobile." In Lecture Notes in Electrical Engineering, 293–301. Singapore: Springer Singapore, 2017. http://dx.doi.org/10.1007/978-981-10-3527-2_26.
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Crean, P. B., T. S. Murty, and J. A. Stronach. "The Fine Grid Model: GF3." In Mathematical Modelling of Tides and Estuarine Circulation, 115–28. Berlin Heidelberg New York: Springer-Verlag, 2013. http://dx.doi.org/10.1002/9781118669167.ch5.
Full textConference papers on the topic "Gf30"
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Schaaf, A., M. De Monte, C. Hoffmann, M. Vormwald, and M. Quaresimin. "Damage mechanisms in PBT-GF30 under thermo-mechanical cyclic loading." In PROCEEDINGS OF PPS-29: The 29th International Conference of the Polymer Processing Society - Conference Papers. American Institute of Physics, 2014. http://dx.doi.org/10.1063/1.4873852.
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Johnson, S., and E. Kerr-Anderson. "Accelerated Tensile-Tensile Fatigue S-N Curve Characterization of PP-GF30 and PA66-GF50 using Block Testing and Cumulative Damage Theory." In CAMX 2023. NA SAMPE, 2023. http://dx.doi.org/10.33599/nasampe/c.23.0132.
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Harvey, R., M. Kauphusman, and E. Kerr-Anderson. "Comparing long term multi-temperature flexural creep with DMA TTSP techniques for neat PP and PP-GF30 long fiber thermoplastic." In CAMX 2023. NA SAMPE, 2023. http://dx.doi.org/10.33599/nasampe/c.23.0146.
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Wang, Qian, Lingyu Sun, Lijun Li, and Le Shen. "Hygrothermal Degradation of GFRP/HSS Interface in Metal-Polymer Hybrid Structures." In ASME 2016 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2016. http://dx.doi.org/10.1115/imece2016-65779.
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Polymer-metal hybrid (PMH) by over-molding is a kind of weight reduction technology, in which the interface is formed by injecting liquid polymer directly on the surface of stamped metal and then curing under pressure. This technique takes the advantages of both the high strength and stiffness of metal and the complex geometry formability of polymer, and it is usually applied in structural components for weight reduction compared to all-metal structure. However, the different coefficient of thermal expansion (CTE) or hygroscopicity for polymer and metal in PMH structure may possibly produce additional interface stress and decrease joining strength degradation, and finally lead to local separation or complete fracture under various environmental loads. The present paper will provide an effective numerical method and investigate the influence of temperature and humidity on the onset and growth of crack, as well as the degradation of interface fracture toughness in PMH structures. Additionally analytical analysis provides qualitative guidelines and orientation for numerical method. The crack initiation is studied by the tensile test of a lap joint specimen, and the crack growth is studied by the DCB (Double Cantilever Beam) test and ENF (End Notched Flexure) test and of PMH specimen with an initial crack. It proves that both temperature and humidity has a great influence on interfacial strength, ultra bearing capacity and energy release rates of PMH structures, and their coupling has more influence than a single factor. The interface degradation degree of the GF30/PA66-HSS is lower than that of PA66-HSS under the same hygrothermal environment.
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Yin, Di, Bing Han, Jili Sun, Aiping Chen, Liangbo Zhao, Xinzhe Yuan, Lihua Zhong, and Yuxin Hu. "A TOPSAR Calibration Method For Processing System Of GF3 Next Generation." In 2019 6th Asia-Pacific Conference on Synthetic Aperture Radar (APSAR). IEEE, 2019. http://dx.doi.org/10.1109/apsar46974.2019.9048472.
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Guo, Li, Xia Wang, Yizhe Wang, and Mingyu Yue. "A New Approach of Digital Orthorectification Map Generation for GF3 Satellite Data." In 2019 6th Asia-Pacific Conference on Synthetic Aperture Radar (APSAR). IEEE, 2019. http://dx.doi.org/10.1109/apsar46974.2019.9048267.
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Clarke, S., V. Lock, J. Duddy, JH Newman, and JR Kirwan. "SAT0068 Intra-articular hylan gf20 (synvisc) in the management of patellofemoral osteoarthritis of the knee (poak)." In Annual European Congress of Rheumatology, Annals of the rheumatic diseases ARD July 2001. BMJ Publishing Group Ltd and European League Against Rheumatism, 2001. http://dx.doi.org/10.1136/annrheumdis-2001.443.
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Farzaneh, S., A. Kallel, M. Shirinbayan, J. Fitoussi, and A. Tcharkhtchi. "Effect of cryogenic conditions on mechanical properties of polypropylene composite (GF50-PP) produced by thermocompression process." In PROCEEDINGS OF THE 37TH INTERNATIONAL CONFERENCE OF THE POLYMER PROCESSING SOCIETY (PPS-37). AIP Publishing, 2023. http://dx.doi.org/10.1063/5.0169116.
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Guo, Li, Xia Wang, and Mingyu Yue. "Improved Digital Orthorectification Map Generation Approach Using the Integrating of ZY3 and GF3 Image." In 2020 IEEE 5th International Conference on Image, Vision and Computing (ICIVC). IEEE, 2020. http://dx.doi.org/10.1109/icivc50857.2020.9177473.
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Sato, Koji, Shinya Kurokawa, and Toshiyuki Sawa. "Visco-Elastic FEM Stress Analysis of Bolted Flange Connections With PTFE-Blended Gaskets Under Elevated Temperature." In ASME 2012 Pressure Vessels and Piping Conference. American Society of Mechanical Engineers, 2012. http://dx.doi.org/10.1115/pvp2012-78395.
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Bolted flange connections with gaskets have been used under high temperature and long-term conditions. Sometimes leakage accidents occur from the gasket interfaces due to the creep and relaxation phenomena. In the present paper, the changes of the gasket stress in bolted flange connections under high temperature conditions for a long-term are analyzed using FEM calculations taking into account the gasket temperature dependency. The gaskets used are PTFE-blended (V#GF300). It’s shown that the effect of the temperature on the stress-strain relationship of the gasket is substantial. The changes in the gasket stress of the connections for 12 months are analyzed using the FEM. The effects of nominal diameter of flanges, retightening and the fluid temperature (20 to 300 °C) on the change of gasket stress in the connections under elevated temperature are examined using the FEM calculations. It is found that the reduction in the gasket stress is over 40%. In addition, experiments to measure the axial bolt force were carried out. The calculated results are in a fairly good agreement with the experimental results. The results reveal that the long-term behavior of the bolted flange connections can be estimated in our study. Discussion is made on the effects of the bolt preload and retightening on the reduction of the gasket stress and the sealing performance.
Reports on the topic "Gf30"
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พิมพิทักษ์, อุมาพร, ทรงจันทร์ ภู่ทอง, กิตตินันท์ โกมลภิส, นันทิกา คงเจริญพร, and อณุมาศ บัวเขียว. การพัฒนาแถบทดสอบสำเร็จรูปสำหรับตรวจติดตามระดับฮอร์โมนโพรเจสเทอโรนในน้ำนมโค. สถาบันวิจัยเทคโนโลยีชีวภาพและวิศวกรรมพันธุศาสตร์ จุฬาลงกรณ์มหาวิทยาลัย, 2015. http://dx.doi.org/10.58837/chula.res.2015.2.
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การผลิตน้ำนมและการสืบพันธ์ของโคนม จะมีประสิทธิภาพได้โดยการเพิ่มอัตราการผสมติด ซึ่งสามารถทำได้โดยการผสมเทียมในช่วงระยะที่แม่โคเป็นสัด เพื่อให้แม่โคผลิตน้ำนมเป็นไปอย่างต่อเนื่องการตรวจดังกล่าวสามารถทำได้โดยการวัดระดับฮอร์โมนโพรเจสเทอโรน (progesterone) เพื่อให้สามารถกำหนดวันผสมพันธุ์ที่ถูกต้องและเป็นการเพิ่มโอกาสการตั้งท้องของแม่โคให้ต่อเนื่อง พบว่าปัจจุบันได้นิยมนำเอาการวัดระดับโพรเจสเทอโรนในน้ำนมด้วยวิธี ELISA ซึ่งเป็นวิธีที่เหมาะแก่การวัดตัวอย่างจำนวนมากในระดับห้องปฏิบัติการทั่วไป แต่เพื่อความรวดเร็วในการตรวจสอบผลในระดับภาคสนาม ในการศึกษาครั้งนี้จึงได้พัฒนาแถบทดสอบสำเร็จรูปต้นแบบเพื่อใช้ตรวจหาปริมาณฮอร์โมนโพรเจสเทอโรน ให้เหมาะแก่การใช้งานในระดับภาคสนามของเกษตรกร โดยใช้หลักการ Immunochromatographic Assay test strip (ICA) เป็นรูปแบบ Competitive inhibition จากการทดลองพบว่าแถบทดสอบต้นแบบประกอบด้วย 4 ส่วนได้แก่ (1) ส่วนบริเวณ Absorbance pad ซึ่งเป็นส่วนดูดซับตัวอย่างส่วนเกินเลือกใช้ CF7 ของ Whatman® (2) ส่วนบริเวณ Reaction pad เป็นส่วนที่เกิดการจับของแอนติเจนกับแอนติบอดีใช้ Membrane AE100 ของ Whatman® ประกอบด้วยบริเวณของ Control line ตรึงด้วย Goat Anti-Mouse IgG Fc (specific) และ Test line ตรึงด้วยโพรเจสเทอโรนเชื่อมต่อกับ BSA ความเข้มข้น 0.5 และ 1 ไมโครกรัมต่อมิลลิลิตร ตามลำดับ โดยใช้ปริมาตร 0.2 ไมโครลิตรต่อแถบทดสอบหรือ 0.5 ไมโครลิตรต่อความกว้าง 1 เซนติเมตร (3) บริเวณ Conjugate pad ใช้ แอนติบอดีต่อโพรเจสเทอโรน 31.25 ไมโครกรัมต่อมิลลิลิตร ติดกับอนุภาคทอง ขนาด 20 นาโนเมตร ปริมาตร 2 ไมโครลิตร เคลือบบน GF33 ของ Whatman® เมื่อทำการศึกษาวัสดุอุปกรณ์ที่ใช้ช่วยตรึงแอนติเจนและแอนติบอดีบนแถบทดสอบได้แก่ กระจกสไลด์ ปากกาหมึกซึมและเครื่องมือ Dispense workstation เมื่อนำแถบทดสอบที่เตรียมได้ไปทดสอบกับสารละลายมาตรฐาน P4 ผลที่ได้คือสีของเส้นทดสอบจะลดลงเมื่อทดสอบกับสารละลายมาตรฐาน P4 ที่ความเข้มข้น 3.9, 125 และ 3.9 นาโนกรัมต่อมิลลิลิตร ตามลำดับ เมื่อใช้เครื่อง Dispense workstation พบว่าแถบสีที่ได้มีความคมชัด เมื่อทดสอบกับสารมาตรฐาน P4 ที่ความเข้มข้นต่ำ สามารถมองเห็นความแตกต่างอย่างชัดเจนเมื่อเทียบกับตัวควบคุม โดยแถบสีจะแปรผันตามปริมาณ โพรเจสเทอโรน ดังนั้นแถบทดสอบต้นแบบที่เตรียมได้จึงสามารถนำไปทดสอบการใช้งานในการตรวจระดับฮอร์โมน โพรเจสเทอโรน จากตัวอย่างน้ำนมโคได้ ต่อไป
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Sreedhara, Sindhu, Adam Brandt, and Jingfan Wang. PR-681-18701-R01 Evaluating the Use of Optical Gas Imaging Cameras for Above Ground Facilities. Chantilly, Virginia: Pipeline Research Council International, Inc. (PRCI), December 2020. http://dx.doi.org/10.55274/r0011989.
Full textAbstract:
Natural gas is the largest primary energy source in the United States. Reliance on natural gas is only increasing as its role in electricity systems becomes more significant and that of coal diminishes. While this has air quality and health benefits over the use of coal, the global warming potential of methane - the primary component of natural gas - cannot be ignored. In order to mitigate methane leaks, periodic leak detection and repair programs are required in the United States. Various different technologies exist to detect and/or quantify methane leaks. Studying them and evaluating their performance is an important step in evaluating equivalence in emissions reductions between technologies. In this study, we evaluate the performance of two optical gas imaging cameras. The first is the FLIR GF320, an infrared camera, which we coupled with the Providence Photonics QL320 to enable it to quantify methane leaks. The second is the Rebellion Photonics mini-GCI, a hyperspectral imaging camera, which provides automated alerts when a leak is detected. Experiments to test the two systems were carried out at the Methane Emissions Technology Evaluation Center in Fort Collins, Colorado over two weeks. We tested both technologies at a variety of leak size and imaging distance combinations. In order to better simulate real-world conditions, we also tested the performance of the two systems in the presence of different types of interference. For the first technology, we evaluate the quantification performance and for the second, the detection performance. We report performance metrics at different distances, interference scenarios and leak sizes in the case of Rebellion. The two technologies differ in terms of automation, detection and quantification capabilities, imaging distance and minimum observable leak size.