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Статті в журналах з теми "Debond effect":
1
Sikdar, Shirsendu, Abhishek Kundu, Michał Jurek, and Wiesław Ostachowicz. "Nondestructive Analysis of Debonds in a Composite Structure under Variable Temperature Conditions." Sensors 19, no. 16 (August 7, 2019): 3454. http://dx.doi.org/10.3390/s19163454.
Анотація:
This paper presents a nondestructive analysis of debonds in an adhesively-bonded carbon-fibre reinforced composite structure under variable temperature conditions. Towards this, ultrasonic guided wave propagation based experimental analysis and numerical simulations are carried out for a sample composite structure to investigate the wave propagation characteristics and detect debonds under variable operating temperature conditions. The analysis revealed that the presence of debonds in the structure significantly reduces the wave mode amplitudes, and this effect further increases with the increase in ambient temperature and debond size. Based on the debond induced differential amplitude phenomenon, an online monitoring strategy is proposed that directly uses the guided wave signals from the distributed piezoelectric sensor network to localize the hidden debonds in the structure. Debond index maps generated from the proposed monitoring strategy show the debond identification potential in the adhesively-bonded composite structure. The accuracy of the monitoring strategy is successfully verified with non-contact active infrared-thermography analysis results. The effectiveness of the proposed monitoring strategy is further investigated for the variable debond size and ambient temperature conditions. The study establishes the potential for using the proposed damage index constructed from the differential guided wave signal features as a basis for localization and characterization of debond damages in operational composite structures.
2
Varna, Janis, Lin Qi Zhuang, Andrejs Pupurs, and Zoubir Ayadi. "Growth and Interaction of Debonds in Local Clusters of Fibers in Unidirectional Composites during Transverse Loading." Key Engineering Materials 754 (September 2017): 63–66. http://dx.doi.org/10.4028/www.scientific.net/kem.754.63.
Анотація:
Fiber/matrix debonding in transverse tensile loading of a unidirectional composite is analyzed calculating energy release rate (ERR) for interface crack propagation. Non-uniform fiber distribution (local hexagonal fiber clustering) is assumed in the model. The matrix region containing the central fiber with the debond and the 6 surrounding fibers is embedded in a large block of homogenized composite which has the same fiber content as the region analyzed explicitly. Some of the fibers surrounding the central fiber may also have a debond. The effect of the local clustering and of the presence of other debonds on magnification of the ERR is analyzed.
3
Quispitupa Yupa, A., and C. Berggreen. "Effect of Initial Debond Crack Location on the Face/core Debond Fracture Toughness." EPJ Web of Conferences 6 (2010): 24004. http://dx.doi.org/10.1051/epjconf/20100624004.
4
Gong, Wen Ran, Jin Long Chen, and Jiao Wang. "Debond Propagation in Honeycomb Structure under Pure Bending Load." Applied Mechanics and Materials 37-38 (November 2010): 284–87. http://dx.doi.org/10.4028/www.scientific.net/amm.37-38.284.
Анотація:
This paper used Finite Element Method to investigate the influence of the circular face-core debonding dimension on the further debond propagation under the pure bending load in honeycomb structure. We also summarized the debonding rules and looked further into debonding area effect on the critical load for debond propagation. The conclusions are as follows: For a honeycomb panel, there exists a certain debonded radius . When the initial debonded radius is greater than , it will experience local buckling which takes the form of snap-through buckling. The debonding propagation is only discovered on the wide direction of the plate. The critical load for debonding propagation decreases with increased debond size.
5
Turk, Tamer, Selma Elekdag-Turk, Devrim Isci, Fethiye Cakmak, and Nurhat Ozkalayci. "Saliva Contamination Effect on Shear Bond Strength of Self-etching Primer with Different Debond Times." Angle Orthodontist 77, no. 5 (September 1, 2007): 901–6. http://dx.doi.org/10.2319/100906-415.
Анотація:
Abstract Objective: To evaluate shear bond strengths (SBSs) of a self-etching primer (SEP) following saliva contamination at different stages of bonding at debond times of 5, 15, and 30 minutes and 24 hours. Materials and Methods: Two-hundred forty human premolars were divided into four groups: group 1, uncontaminated; group 2, saliva contamination after priming; group 3, saliva contamination before priming; and group 4, saliva contamination before and after priming. Four subgroups according to debond times of 5, 15, 30 minutes and 24 hours were composed. Metal brackets were bonded with an SEP (Transbond Plus) and light-cure adhesives paste (Transbond XT). SBS values and the adhesive remnants were determined. Results: The highest SBS was obtained at a debond time of 24 hours for the control group. This was significantly different from the other groups. SBSs at 5, 15, and 30 minutes showed no significant difference from each other in the control group (P > .05). Lowest SBSs were obtained at a debond time of 5 minutes for groups 1, 2, 3, and 4 (8.38, 7.10, 7.06, and 6.26 MPa, respectively) and were not significantly different from each other (P > .05). SBSs at 24 hours were not significantly different from each other for groups 2, 3, and 4 (P > .05). Significant differences were found in the adhesive remnant (P < .001). Conclusions: SEP (Transbond Plus) may produce clinically acceptable bracket bonding after 5, 15, and 30 minutes from time of placement on the teeth, even with light and heavy saliva contamination.
6
Turk, Tamer, Selma Elekdag-Turk, and Devrim Isci. "Effects of Self-Etching Primer on Shear Bond Strength of Orthodontic Brackets at Different Debond Times." Angle Orthodontist 77, no. 1 (January 1, 2007): 108–12. http://dx.doi.org/10.2319/011606-22r.1.
Анотація:
Abstract Objective: To evaluate the effect of a self-etching primer on shear bond strengths (SBS) at the different debond times of 5, 15, 30, and 60 minutes and 24 hours. Materials and Methods: Brackets were bonded to human premolars with different etching protocols. In the control group (conventional method [CM]) teeth were etched with 37% phosphoric acid. In the study group, a self-etching primer (SEP; Transbond Plus Self Etching Primer; 3M Unitek, Monrovia, Calif) was applied as recommended by the manufacturer. Brackets were bonded with light-cure adhesive paste (Transbond XT; 3M Unitek) and light-cured for 20 seconds in both groups. The shear bond test was performed at the different debond times of 5, 15, 30 and 60 minutes and 24 hours. Results: Lowest SBS was attained with a debond time of 5 minutes for the CM group (9.51 MPa) and the SEP group (8.97 MPa). Highest SBS was obtained with a debond time of 24 hours for the CM group (16.82 MPa) and the SEP group (19.11 MPa). Statistically significant differences between the two groups were not observed for debond times of 5, 15, 30, or 60 minutes. However, the SBS values obtained at 24 hours were significantly different (P < .001). Conclusions: Adequate SBS was obtained with self-etching primer during the first 60 minutes (5, 15, 30 and 60 minutes) when compared with the conventional method. It is reliable to load the bracket 5 minutes after bonding using self-etching primer (Transbond Plus) with the light-cure adhesive (Transbond XT).
7
Stasio, Luca Di, Janis Varna, and Zoubir Ayadi. "Effect of the proximity to the 0°/90° interface on Energy Release Rate of fiber/matrix interface crack growth in the 90°-ply of a cross-ply laminate under tensile loading." Journal of Composite Materials 54, no. 21 (March 22, 2020): 3021–34. http://dx.doi.org/10.1177/0021998320912810.
Анотація:
Models of Representative Volume Elements of cross-ply laminates with different geometric configurations and damage states are studied. Debond growth is characterized by the estimation of the Mode I and Mode II Energy Release Rate using the Virtual Crack Closure Technique. It is found that the presence of the [Formula: see text] interface and the thickness of the [Formula: see text] layer has no effect, apart from laminates with ultra-thin [Formula: see text] plies where it is however modest. The present analysis supports the claim that debond growth is not affected by the ply-thickness effect.
8
Sutcu, M., and W. B. Hillig. "The effect of fiber-matrix debond energy on the matrix cracking strength and the debond shear strength." Acta Metallurgica et Materialia 38, no. 12 (December 1990): 2653–62. http://dx.doi.org/10.1016/0956-7151(90)90278-o.
9
Ziao, J., and J. Tao. "Investigation of Interlaminar Defects and their Influence on Interlaminar Strength." Advanced Composites Letters 5, no. 4 (July 1996): 096369359600500. http://dx.doi.org/10.1177/096369359600500404.
Анотація:
In this paper, we directed our attention to the interlaminar defects and their influence on the interlaminar strengths. With the aid of a S-570 scanning electron microscope, the morphology and distribution of interlaminar defects were inspected and documented. According to their shape, size and cause of formation, the defects were classified into five types: flakiness void, irregular shaped debond, local imperfectly cured resin, debond in two multi-directional plies, and inhomogeneous fibers and the large scale debond by these fibers. The cause of defects formation was discussed by analyzing the manufacturing process of composites. The influence of defects on the interlaminar strength and its mechanism was analyzed experimentally and theoretically. The results indicate that these defects, with different effects, decrease the interlaminar strength because they form interlaminar cracks, and the interlaminar shear strength is less affected than interlaminar tensile strength, which is measured according to GB4944 test method. To comprehend defects distribution effect, a four-point-bending test method was introduced to measure the interlaminar peel strength, and a discussion was made on the correlation between the interlaminar tensile strength, interlaminar peel strength and in-plane transverse tensile strength. Finally the concept of interlaminar defect coefficient, which can be used to characterize the defects, was set up and the formula to calculate it was proposed.
10
Medalia, Avrom I. "Effect of Carbon Black on Ultimate Properties of Rubber Vulcanizates." Rubber Chemistry and Technology 60, no. 1 (March 1, 1987): 45–61. http://dx.doi.org/10.5254/1.3536121.
Анотація:
Abstract In this survey, we have concluded that carbon black reinforces ultimate properties of rubber by tear deviation. This can occur at the colloidal level, as the tear is forced to pass around carbon black aggregates, thus increasing the area of the torn surface. Colloidal tear deviation may be the cause of the increase in threshold tearing energy which appears to be a small but significant component of reinforcement. Most reinforcement under ordinary test conditions is due to macroscopic tear deviation. This appears to be caused by strands of carbon black aggregates which force the growing tear to change direction. Macroscopic tear deviation is readily observed in a trouser tear test as stick-slip or knotty tear. In the tensile strength test, tear deviation prevents catastrophic rupture until a high stress is reached. In order to be effective in this or other ultimate properties, the carbon black must not debond; i.e., failure must go through the rubber rather than through the debonded rubber—filler interface. Reinforcing carbon blacks do not debond (from diene rubbers) under normal conditions and so do not require further strengthening of the rubber—filler bonds.
Дисертації з теми "Debond effect":
1
Lord, Charles. "Damping effects of debonded composites." Thesis, University of Sheffield, 2012. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.577524.
Анотація:
Numerical simulations and analytical models are increasingly being sought for the design and behaviour prediction of composite materials. The use of high-performance composite materials is a growing area particularly in civilian and defence related applications. This growth demands the understanding and ability to predict how these materials will behave under their exposed environments. In this thesis, the displacement behaviour of naturally debonded composites (NDCs) from out-of-plane bending conditions is investigated. A detailed experimental programme is conducted to ascertain the phenomenological behaviours of these systems from steady-state responses for forced harmonic loading and freevibrations. The stiffness and energy dissipation behaviour are examined and a finite element (FE) model describing their behaviour is developed. Using the FE model, the experimental programme is extended through simulations and analytical models are developed to predict the displacement response behaviour. Through the exploitation of the analytical models, a linearisation is used to extract the bulk effective material properties and a constitutive model is developed to describe multi-layered 0JDCs that are reduced to a single layer describing their steady-state responses. The friction between each of the layers is included in the analytical model and is shown to have distinct behaviour for these types of composites. Acceptable agreement is observed between the analytical model predictions, the FE model and the experiments. It is well known that prevention of failure for vibratory exposed structures is a continuing challenge and that although the characterisation of damping in vibrating structures has long been an active area of research in structural dynamics, it is usually limited to experimental data. As the exploitation of lighter and more efficient structures is becoming more prevalent, the need for alternative damping materials and systems is overwhelmingly necessary. The use of NDCs poses as a viable candidate for rectifying some of these challenges, particularly since they can be designed with high levels of accuracy as opposed to a rough estimation as with many damping systems. From this work it is shown that layered NDCs have the ability to dissipate large amounts of energy from exploiting their frictional interfaces. There are many areas that NDCs could serve to be useful as damping systems.
2
Assouly, Laurent. "La sobriété à l’épreuve de nouvelles migrations urbaines de télétravailleurs : impact sur la consommation et la représentation des idéaux de vie." Electronic Thesis or Diss., Université Paris-Panthéon-Assas, 2023. http://www.theses.fr/2023ASSA0069.
Анотація:
La sobriété est ce terme polysémique présenté par la recherche académique et les médias comme le scénario incontournable de la transition écologique. Son acception contemporaine englobe une multitude de sens : la frugalité, la tempérance, la simplicité volontaire, qui désignent plusieurs régulations possibles de nos consommations matérielles. Ce travail de thèse instruit et met à l’épreuve la notion de sobriété en s’appuyant sur des enquêtes de terrain qui s’intéressent aux « migrations urbaines de télétravailleurs en ruralité ». Un départ en territoire rural fondé sur des motivations matérialistes et affectives. Nous étudions le rapport subjectif à la consommation et les représentations des idéaux de vie des digitaux-néo-ruraux. Ce néologisme définit cette nouvelle figure du salarié digital à cheval entre plusieurs territoires, entre modernisme et retour à la terre. Nos enquêtes relatent une sobriété expérientielle qui montre plusieurs opérationnalités possibles de ce concept réductionniste : « effet débond », « consommation territorialement responsable », « autre rapport au temps », « sobriété contingente », « hub domestique ». La sobriété dévoile plusieurs facettes à même d’élargir sa désirabilité. L’acculturation est gérée par des stratégies d’intégration où la consommation est utilisée pour légitimer son affiliation territoriale. Notre recherche montre des digitaux-néo-ruraux qui articulent enjeux environnementaux, technologiques, économiques et sociétaux. Ce travail de thèse permet de mieux comprendre la construction d’autres modes et imaginaires de vie avec une logique de l’abondance qui est questionnéeSufficiency is a polysemous term presented by academic research and the media as the essential scenario for ecological transition. Its contemporary meaning encompasses a multitude of meanings: frugality, temperance, voluntary simplicity, all of which refer to possible ways of regulating our material consumption. This thesis examines and tests the notion of sufficiency by drawing on field research into the 'urban migration of teleworkers'. A move to rural areas based on materialistic and affective motivations.We are studying the subjective relationship to consumption and the representations of the ideals of life of the digital-neo-rural. This neologism defines this new figure of the digital employee straddling several territories, between modernism and a return to the land.Our surveys reveal an experiential sufficiency that shows several possible operationalities of this reductionist concept: "debond effect", "territorially responsible consumption", "another relationship with time", "contingent sufficiency", "domestic hub". Sufficiency has a number of facets that can broaden its desirability. Acculturation is managed by integration strategies in which consumption is used to legitimise territorial affiliation. Our research shows that digital-neo-rural living combines environmental, technological, economic, and societal issues. This thesis provides a better understanding of the construction of alternative lifestyles and imaginaries, with the logic of abundance being called into question
3
Schilling, Jennifer K. "High Pressure Hydrodynamic Shock Wave Effects on Tenderness of Early Deboned Broiler Breasts." Thesis, Virginia Tech, 2000. http://hdl.handle.net/10919/31010.
Анотація:
Breast muscles that are deboned prior to 4 to 6 h postmortem are highly variable and lacking in tenderness. The poultry industry currently provides costly storage space for intact broiler breasts during this 4 to 6 h period. This thesis evaluates tenderization techniques that if effective could eliminate the need for this additional 4 to 6 h storage time. The first objective of this study was to determine a relationship between Warner-Bratzler shear values (WBS) (1 cm by 1cm, variable length strips) and consumer tenderness acceptability of broiler breasts. The breasts were divided into five groups based on their WBS values. Consumers were presented with one sample (1 cm by 1 cm by 2 cm strips) at a time and asked to report the acceptability of the sample's tenderness on a 9-point hedonic scale. Of the 62 panelists, 93.5 % found chicken breasts with WBS values from 2.1 to 3.1 kg to be acceptable. Only 83.9 % of the panelists found the extremely tender chicken breast to be acceptable (1.1 to 1.9 kg). The percentage of consumers that found the samples acceptable decreased as the WBS values increased beyond 3.1 kg (P<0.05).
The second objective determined the effects of high pressure hydrodynamic shockwave (HSW) on tenderness (48 h postmortem) of early-deboned (52 min postmortem) breasts treated 25 minutes after deboning (70 min postmortem) or treated after storage (24 hr postmortem) and compared to the corresponding non-treated companion breasts. The effect of HSW treatment on early-deboned treated 25 min after deboned broiler breasts was determined by the following methods. Live broiler chickens were obtained from a commercial poultry company and slaughtered according to commercial processing standards. The effect of HSW on early deboned stored broiler breast was examined by deboning broiler breasts 45 min postmortem and storing (4 C) for 24 h. One breast from each bird was treated with hydrodynamic shockwave, while the companion breast was used as a control. Packaged breasts were placed in the center of a 20.23 cm diameter cylinder which was vertically positioned in the bottom of a water-filled HSW hemishell tank (30.4 cm diameter) and a shockwave was produced by and a shockwave was produced by detonating 40 grams of molecular explosive in the water. Early deboned (ED) breasts stored 24 h before treatment (2.5 kg, WBS) were 42% more tender than the companion ED control breasts (4.3 kg, WBS). The HSW treated breasts would be acceptable to approximately 94 % of consumers. The ED control breasts would be acceptable to only 67.7% of consumers. Early deboned and treated 25 min after deboning breasts (5.0 kg) were not different in WBS from their companion ED control breasts (4.6 kg). Early-deboned breasts treated immediately may require higher pressure shockwaves or delayed treatment. The HSW process can overcome the problem with tenderness associated with early deboning if the breasts are processed after storage thereby providing processors with the option to debone earlier.
A third objective was to examine the effects of electrically produced shockwaves on early deboned broiler breasts and normally processed turkey breast. Broiler breasts were treated with one Pulse Firing Network (PFN) or two PFN and 45 % Energy. Breasts treated with one PFN were not different than controls. Broiler breasts exposed to two PFN were 22 % more tender and different from the controls. Turkey breast portions exposed to two PFN and 72% Energy were different (12 % lower WBS values) from the control breast portion. Electrically produced shockwaves can tenderize stored, early deboned chicken breasts and aged turkey breasts.Master of Science
4
Melo, van Lent Debora [Verfasser]. "Food for thought : The effect of nutrition on dementia and memory decline / Debora Melo van Lent." Bonn : Universitäts- und Landesbibliothek Bonn, 2018. http://d-nb.info/1218301635/34.
5
Liu, Jin. "Effects of Chemical Additives on the Light Weight Paper." Diss., Georgia Institute of Technology, 2004. http://hdl.handle.net/1853/7626.
Анотація:
Tissue, among the highest value added paper products, finds extensive application in modern society. Continued efforts are being made to further improve tissue properties, such as strength, softness and water absorbency. Besides the efforts on characterizing facial tissue softness, this study focuses on tissue quality improvement through chemical means. The application of a wet strength resin, Kymene1500 and a debonding agent, Softrite7516 onto cellulose fibers is considered.
First, the adsorption kinetics of the two chemical additives onto cellulose fibers was studied. The adsorption mechanisms were proposed and validated by kinetic data. A novel apparatus was designed in this study, and represented the first in the field to collect real-time data, which has the potential to be applied to the adsorption kinetic study of other types of paper additives.
Second, the effects of Kymene1500 and Softrite7516 on various sheet properties were studied. The results provide quantitative information on tissue additives effects on sheet properties. It is shown that the combined application of the additives can overcome the disadvantages of individual species and produce sheets with both wet strength and softness.
Finally, environmental-benign debonding agents with polyoxyethylene chains were applied to the sheets, and the effects of two design parameters, i.e., fatty acid and degree of ethoxylation, on tissue properties were investigated.
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Vieira, Débora Gleice da Silva Del Rio [Verfasser], Schäfer [Akademischer Betreuer] Michael, and Tropea [Akademischer Betreuer] Cameron. "Numerical simulation of aerodynamic plasma actuator effects / Debora Gleice da Silva Del Rio Vieira. Betreuer: Schäfer Michael ; Tropea Cameron." Darmstadt : Universitäts- und Landesbibliothek Darmstadt, 2013. http://d-nb.info/1107771420/34.
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Desideri, Debora [Verfasser]. "Dependency of non-invasive brain stimulation effects on real-time EEG-based measurements of instantaneous excitability in human motor cortex / Debora Desideri." Tübingen : Universitätsbibliothek Tübingen, 2021. http://d-nb.info/1227924526/34.
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Albertsen, Inke. "Effects of haptic supplementation on postural stability in standing, perturbed standing and sitting in older adults." Thesis, Aix-Marseille, 2012. http://www.theses.fr/2012AIXM4099.
Анотація:
Le présent travail portait sur l'étude des effets de la supplémentation haptique sur la stabilité posturale debout et assise du sujet jeune et âgé. La question si les informations haptiques fournies par un support mobile améliorent la stabilité autant qu'un support fixe a peu été étudiée. Le présent travail visait à contribuer à une meilleure compréhension des mécanismes sous-jacents à l'effet stabilisateur potentiel d'un support type « canne mobile ». Les analyses portaient sur le centre de pression (COP). Les résultats des premières deux études confirment notre hypothèse générale sur l'effet de la supplémentation haptique indépendant de l'âge et de la mobilité du support. Si une résistance suffisante est fournie à l'opposé des oscillations du corps par le support les participants amélioraient leur stabilité. Dans la troisième étude, nous avons également manipulé des entrées visuelles et les résultats suggèrent qu'un manque de vision peut être compensé par la supplémentation. Dans la quatrième étude, nous avons également analysé la coordination inter-segmentaire. Les résultats suggèrent un meilleur contrôle postural avec la supplémentation alors qu'elle n'influence pas la coordination inter-segmentaire. La cinquième étude visait à déterminer si la supplémentation permettait d'améliorer la robustesse du système à des perturbations. Les résultats suggèrent que les sujets jeunes réduisent le temps de la première correction du COP avec la supplémentation alors que les sujets âgés corrigent leur COP plus tôt que les jeunes et ne bénéficient pas de cette dernière. Les résultats expérimentaux laissent envisager l'application du paradigme « canne mobile » à la locomotionThis work was dedicated to the study of the effects of haptic supplementation on postural stability of young and old adults during standing and sitting tasks. The question of whether haptic information provided by a mobile support improves stability similar to a fixed support has been rarely studied. The present work aimed to contribute to a better understanding of the underlying mechanisms of the potential stabilizing effect of haptic information provided by a cane-like support. The analysis focused on the center of pressure (COP). The results of the first two studies confirmed our general hypothesis about the effect of haptic supplementation independent of age and the mobility of the support. If sufficient resistance is provided by the support against body sway participants improved their postural stability. In the third study, we also manipulated visual inputs and the results suggested that a lack of vision can be compensated due to supplementation. In the fourth study, we also analyzed the inter-segmental coordination. The results suggested a better postural control due to supplementation whereas it does not affect the inter-segmental coordination. The fifth study aimed to determine whether haptic supplementation improves the system's robustness to sudden perturbations. The results suggested that only young participants reduce the time to the first COP correction due to supplementation while elderly correct the COP earlier than young adults, even without additional haptic information, and therefore do not benefit from haptic supplementation. Overall, the experimental results open the way for the application of the “mobile-stick” experimental paradigm to locomotion
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Chabeauti, Pierre-yves. "Adaptation des représentations internes de l’action à la microgravité : continuum fonctionnel de la perception à l’exécution." Thesis, Aix-Marseille, 2012. http://www.theses.fr/2012AIXM4730/document.
Анотація:
Quel rôle joue la gravité dans les représentations internes de l'action ? Au-delà des contraintes d'équilibre, le vecteur gravitaire influence-t-il l'action de façon globale, jusqu'à la perception des mouvements de nos semblables ? Ces questions ont été celles qui ont guidé mes travaux de thèse. L'originalité de notre approche a été de placer l'exécution et la perception de l'action dans un « continuum fonctionnel » s'articulant autour des représentations internes de l'action. Pour ce faire, l'outil de choix qui est commun aux trois expériences de cette thèse est la microgravité (0G). Les expériences de cette thèse ont montré que les représentations internes de l'action se nourrissaient des informations graviceptives pour se construire et s'adapter constamment. Cependant, dans certaines conditions telle que la 0G à court terme, apparaît un ordre de priorité. En effet, le SNC est capable de mettre en place des solutions immédiates et efficaces pour l'exécution, comme en témoigne la repondération sensorielle rapide qui s'opère en 0G dans une tâche d'orientation posturale. Cependant, un temps de latence est observé dans la recalibration des modèles internes sur la base des afférences sensorielles fortement perturbées. C'est ce que nous avons montré grâce à un protocole d'imagerie motrice, mettant en évidence une perte de l'isochronie entre les mouvements exécutés et imaginés en 0G. Enfin, nous avons mis en évidence, chez des sujets sans expérience aucune de microgravité, que la perception du mouvement humain est efficace même lorsque ce dernier est exécuté en apesanteur, bien que des réseaux cérébraux différents soient mis en jeuxWhat is the role of gravity in the internal representations of action? Beyond the constraints of balance, does the gravity vector influence the action globally, up to the perception of our peers' movement? These issues have guided my thesis work. The originality of our approach was to place the execution and the perception of action in a "functional continuum" built around the internal representations of the action. To do this, the tool of choice, that is common to all three experiments presented here, is microgravity (0G). The experiments of this thesis showed that the internal representations of action are fed with graviceptive information to build and adapt constantly. However, under certain conditions such as short-term 0G, an order of priority appears. Indeed, the CNS is able to implement immediate and effective solutions, as we demonstrate it with the fast sensorial reweighting observed during a postural orientation task. However, a lag is observed in the recalibration of internal models based on sensory inputs severely disrupted. This is what we have shown through a protocol of motor imagery, showing a loss of isochrony between executed and imagined movements under 0G. Finally, we have demonstrated in subjects without any experience of microgravity, that the perception of human movement is effective even when it is performed in weightlessness, although different cerebral networks are involved
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Calcinari, Andrea. "Effetti delle onde gravitazionali attraverso la deviazione geodetica." Bachelor's thesis, Alma Mater Studiorum - Università di Bologna, 2017. http://amslaurea.unibo.it/14076/.
Анотація:
L'intento perseguito nel redigere questa tesi è quello di illustrare la teoria alla base delle onde gravitazionali per giungere ad intuire i metodi che ne consentono la rilevazione. Queste sono una conseguenza della Teoria della Relatività Generale di cui si riporta una semplice introduzione nel primo capitolo, sottolineando l'importanza del formalismo geometrico e tensoriale. Le equazioni di Einstein descrivono il campo gravitazionale come curvatura
dello spaziotempo, questa è rappresentata dal tensore di Riemann che determina
in particolare l'accelerazione relativa di due geodetiche. Si studia poi l'approssimazione di campo debole, necessaria per linearizzare le equazioni di Einstein
e per mostrare che la perturbazione metrica soddisfa
un'equazione d'onda. Il capitolo terzo si conclude quindi con un'analogia tra le onde gravitazionali
e quelle elettromagnetiche. Nel quarto capitolo si analizzano le
soluzioni sotto forma di onde piane: qui emergono caratteristiche peculiari riguardanti la perturbazione gravitazionale che, con il giusto gauge, permette di
dedurre che solo due sono le polarizzazioni fisicamente rilevanti e che sono trasversali rispetto
alla direzione dell'onda. Infine si evince che è necessario un sistema di
particelle per la rilevazione di un'onda perchè la grandezza da osservare è la separazione
tra due geodetiche e come questa varia al passaggio dell'onda. In questo modo viene mostrata
la causa degli effetti mareali e si confermano
le caratteristiche della radiazione gravitazionale anticipate in precedenza, come la
polarizzazione e la natura quadripolare. Alcune considerazioni matematiche finali elucideranno
come le proprietà delle onde suggeriscono con naturalezza l'esistenza di una radiazione
di gravità. Infine si accennerà alle idee chiave che hanno
suggerito la costruzione di rilevatori di onde e come questi debbano funzionare. La trattazione
termina con uno sguardo alle recenti scoperte e alle aspettative future.
Книги з теми "Debond effect":
1
S, Johnson W., Everett R. A, and Langley Research Center, eds. Effect of adherend thickness and mixed mode loading on debond growth in adhesively bonded composite joints. Hampton, Va: National Aeronautics and Space Administration, Langley Research Center, 1986.
2
Center, Langley Research, ed. Effect of debond growth on stress-intensity factors in a cracked orthotropic sheet stiffened by a semi-infinite orthotropic sheet. Washington, D.C: National Aeronautics and Space Administration, Scientific and Technical Information Branch, 1986.
3
Ridley, Aaron. The Deed is Everything. Oxford University Press, 2018. http://dx.doi.org/10.1093/oso/9780198825449.001.0001.
Анотація:
Nietzsche is often held to be an extreme sceptic about human agency, keen to debunk it along every dimension. He dismisses the ideas of freedom, autonomy, and morality, we are told, and even the very existence of agents or selves. This book sets out the opposite view. It does so by arguing that Nietzsche was committed to an ‘expressivist’ conception of agency, a conception that contrasts with the ‘empiricist’ orthodoxy and which—partly in virtue of that fact—allows him to develop highly distinctive accounts not only of freedom, autonomy, and morality, but also of selfhood. In the course of the argument, a variety of central Nietzschean themes are revisited—for example, self-creation, the sovereign individual, will to power, Kantian and Christian morality, amor fati—often to unexpected effect. The Nietzsche who emerges from this book has a clear, if demanding, conception of human agency and a robust commitment to the value of human excellencein all of its forms.
4
Goldstein, Myrna Chandler, and Mark A. Goldstein. Healthy Foods. ABC-CLIO, LLC, 2010. http://dx.doi.org/10.5040/9798400662522.
Анотація:
This book presents research findings about 50 foods that are commonly touted as healthy and educates readers about the medical problems they purportedly alleviate or help prevent. It is always in the best interest of those who market foods to make grandiose claims regarding their nutritional value, regardless of whether actual scientific proof exists to support such a claim. Even diligent and educated consumers often have difficulty discerning facts from mere theory or pure marketing hype. As the incidence of childhood obesity in the United States continues to increase at an alarming rate and food costs skyrocket, this book arrives at a perfect time for health-conscious consumers, providing an authoritative reference for anyone looking to make wise eating decisions at home, work, school, or in restaurants. Healthy Foods: Fact versus Fiction is the result of a collaborative effort between a medical doctor and an award-winning journalist and author on nutrition. This book provides actual research findings to shed light on the true benefits of the most popular health foods—and in some cases, debunk misconceptions surrounding certain foods.
5
Ladewig, Jeffrey W. Trade: Neoclassical Liberal Views on Impacts. Oxford University Press, 2018. http://dx.doi.org/10.1093/acrefore/9780190846626.013.351.
Анотація:
International trade is a dynamic and powerful force that affects nearly every individual, business, and nation in the world. Its scope and scale have also made international trade an immense, intense, and perennial subject of interest and inquiry. Some of the foundational works on international trade can be traced back to Adam Smith and David Hume, whose theories sought to debunk the commonly held idea of international trade at the time: mercantilism, which viewed exports as beneficial because they generated an increase in foreign currency and a nation’s wealth, and imports as detrimental because they were thought to decrease a nation’s wealth. Today, the general idea of comparative advantage informs almost all neoclassical economists’ models of international trade. However, neoclassical economists tend to assume that the theoretical benefits of international trade are clear, and thus, often ignore or dismiss the negative impacts of international trade and the studies that challenge their theories. In fact, many countries have not seen the benefits predicted by neoclassical economic theories. This is particularly evident when comparing the effects of international trade across developed and developing countries. Furthermore, there is evidence that international trade has developed along patterns that are not predicted by the traditional theories of comparative advantage. Given these, the practice of trade and its international impact can be much murkier.
Частини книг з теми "Debond effect":
1
Srivalli, G., G. Jamuna Rani, and V. Balakrishna Murthy. "Effect of Debond and Randomness on Thermal Conductivities of Hollow Fiber Composites." In Lecture Notes in Mechanical Engineering, 597–605. Singapore: Springer Singapore, 2020. http://dx.doi.org/10.1007/978-981-15-1307-7_68.
2
Weiss, Hans-Jürgen. "An Estimate of the Reinforcing Effect of Debonded Frictionless Platelets." In Brittle Matrix Composites 3, 328–34. Dordrecht: Springer Netherlands, 1991. http://dx.doi.org/10.1007/978-94-011-3646-4_35.
3
Karihaloo, B. L. "Effect of Partially Debonded Inhomogeneities on the Fracture Toughness of an Elastic Matrix." In Composite Structures 3, 606–20. Dordrecht: Springer Netherlands, 1985. http://dx.doi.org/10.1007/978-94-009-4952-2_43.
4
Wu, Bo, and Jishen Qiu. "Effect of Nano-SiO2 Coating on the Mechanical Recovery of Debonded Fiber-Cement Interface Under Water Curing." In RILEM Bookseries, 879–88. Cham: Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-83719-8_75.
5
McGovern, Thomas F., and Gwo-Jaw Wang. "The Effects of Femoral Component Surface Finish on the Cement Mantle - An in Vitro Study Using a Fully Debonded Model." In Frontiers in Biomedical Engineering, 101–10. Boston, MA: Springer US, 2003. http://dx.doi.org/10.1007/978-1-4419-8967-3_7.
6
Hirschman, Albert O. "Reactionary Rhetoric." In The Essential Hirschman. Princeton University Press, 2013. http://dx.doi.org/10.23943/princeton/9780691159904.003.0013.
Анотація:
This chapter focuses on the common or typical arguments unfailingly made by the great reactive movements of the past two centuries. Emphasis is placed on the major polemical maneuvers engaged in by those who had set out to debunk and roll back “progressive” policies and movements of ideas—by the forces, that is to say, of reaction. Chief among these arguments is what might be called the thesis of the perverse effect. The thesis of the perverse effect is closely connected with the semantic origin of the term reaction, discussed with reference to Newton's Third Law of Motion. From here, the thesis asserts not merely that a movement or policy will fall short of its goal or will occasion unexpected costs or negative side effects, but that the attempt to push society in a certain direction will result in its moving in the opposite direction.
7
Bubbico, Rocco Luigi, Philipp-Bastian Brutscher, and Debora Revoltella. "1. Europe Needs More Public Investment." In A European Public Investment Outlook, 17–32. Open Book Publishers, 2020. http://dx.doi.org/10.11647/obp.0222.01.
Анотація:
The first part sets the stage, providing trends on public investment in France, Germany, Italy and Spain. It is preceded by an initial chapter by Rocco Luigi Bubbico, Philipp-Bastian Brutscher and Debora Revoltella from the European Investment Bank (EIB) outlining the experience of Europe as a whole. The picture is as follows: between 2008 and 2016 public investment in the EU declined from 3.4% of GDP to 2.7%. Despite a slight rebound in 2017 and 2018, public investment still stands at only 2.9% of GDP, 15% below its pre-crisis levels. Fiscal consolidation pressure was at the core of such decline in public investment especially in countries that experienced a strong pressure to tighten their budgets. The negative effect of fiscal consolidation was in many cases amplified by a re-prioritization of public outlays away from investment towards current expenditures. Infrastructure investment was disproportionately affected by the decline in public investment. EIB estimates show that overall infrastructure investment declined by about 25% between 2008 and 2016, with the government sector accounting for the lion’s share of this fall. From a sectorial perspective, investment in transport and education infrastructure experienced the strongest decline. The chapter clearly documents that the fall in government infrastructure investment does not reflect a saturation effect, the annual infrastructure investment gap is estimated to be about €155 bn and that construction of new infrastructure seems to continue to produce large positive economic spillover effects. This chapter advises, as a policy lesson, sound project selection: preparation and implementation are the keys to reversing the negative trend in investment activities in the EU, besides overcoming funding constraints. Obviously, to ensure the efficient use of available funds, sound infrastructure governance is also a key factor.
8
McPherson, Tess. "Spots and acne." In Skin conditions in young people, 11–24. Oxford University Press, 2021. http://dx.doi.org/10.1093/oso/9780192895424.003.0003.
Анотація:
This chapter looks at the process by which spots form on the skin, considering various contributing factors, before then moving on to a discussion of the treatment of spots and acne. It aims to debunk the myth that spots and acne develop just because you are dirty; instead, the way hair follicles become blocked by grease is detailed, and the role of hormones in this process explained. The types of spots that can develop as a result are discussed, and the creams and tablets available to treat these are explained. One tablet treatment—known as isotretinoin—is mentioned in more detail, in order to address the risks, benefits, and side effects of this particular medication.
9
Bryant, Jan. "‘Efficient Market Ideology’." In Artmaking in the Age of Global Capitalism, 29–36. Edinburgh University Press, 2019. http://dx.doi.org/10.3366/edinburgh/9781474456944.003.0005.
Анотація:
This chapter delves into the economic ideologies that were promoted by Milton Friedman and the Chicago School in the latter decades of the 20th century. The financial imperative of the period was based on a false logic: that wealth will trickle down from the very wealthy to eventually advantage all of society. This has led instead to greater inequality between the wealthy and the poor. It has also resulted in the weakening of unionism and precarious working conditions driven by a trend in casualisation. A response to the intensifying effects of capitalism, Guy Debord and the situationists repeatedly updated their ‘spectacle theory’ over many decades, which also included their theory of ‘recuperation’ to address the resilience of capitalism. Various Post War art movements tried to defeat recuperation of their work by the market, but eventually deciding that it was a fruitless enterprise (Ian Burn). If today, all areas of political, social and cultural life are valued only in relation to a financial return, then for art to function as an effective critical political aesthetic today, the economic context needs to be placed under scrutiny. [184]
10
Serraf, Lola. "Supporting and Resisting the Myth of the Blitz." In British Women's Writing, 1930 to 1960, 91–108. Liverpool University Press, 2020. http://dx.doi.org/10.3828/liverpool/9781789621822.003.0006.
Анотація:
Heavily mythologized at the time, the London Blitz is still memorialized in ways that sustain a sense of national pride. The concept was initiated by Angus Calder in The People’s War (1969) which succeeded in bolstering what it attempted to debunk. Lola Serraf uses Susan Ertz’s Anger in the Sky (1943) to reconsider the ‘Myth of the Blitz’, showing how the novel explores conflicting intellectual arguments for, and justifications of, war and airs differing perspectives on British pressure for active American military involvement. Serraf rejects the categorization of Ertz’s novel as propaganda by foregrounding opposing discourses through the conflicting voices of her characters. Calder’s revision of his ideas The Myth of the Blitz, almost half a century after Ertz’s description of the devastating effects of the Blitz on London and on outlying rural English life, helped to deconstruct the image of a wholly patriotic country united in adversity.
Тези доповідей конференцій з теми "Debond effect":
1
Sankar, Bhavani V., Manickam Narayanan, and Abhinav Sharma. "Effect of Core Plasticity on the Post-Buckling Behavior of Debonded Sandwich Beams." In ASME 2000 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2000. http://dx.doi.org/10.1115/imece2000-2025.
Анотація:
Abstract Nonlinear finite element analysis was used to simulate compression tests on sandwich composites containing debonded face sheets. The core was modeled as an elastic-perfectly-plastic material, and the face-sheet as elastic isotropic. The effects of core plasticity, face-sheet and core thickness, and debond length on the maximum load the beam can carry were studied. The results indicate that the core plasticity is an important factor that determines the maximum load.
2
Ma, Q., J. L. Beuth, G. H. Meier, and F. S. Pettit. "The Effect of Conical Indenter Shape on TBC Interfacial Toughness Measurements." In ASME 2007 International Mechanical Engineering Congress and Exposition. ASMEDC, 2007. http://dx.doi.org/10.1115/imece2007-43816.
Анотація:
Thermal barrier coatings (TBCs) are thin ceramic coatings used to insulate gas turbine hot section components. The degradation of interfacial fracture toughness between the coating and the metallic substrate is a key concern for TBC systems. Previous research by the authors has explored the use of conical (Brale) indentation to measure the interfacial fracture toughness of electron beam physical vapor deposition (EB-PVD) TBCs. However, indentation using a standard 120° Brale indenter can fail to yield an ideal debond size for accurate measurement for poorly adhered coatings subjected to long-term thermal exposures, or for as-processed coatings that are well-adhered to the metallic substrate. These limitations of existing conical indentation tests have lead to the study of different shapes of indenters to obtain optimal debond sizes. In this paper, the differences in measuring the interfacial fracture toughness in thermal barrier coating systems due to indentation by rigid cones with various tip angles, namely, 60°, 90°, 120°, and 150° are addressed. Interfacial stress intensity factor distributions, i.e., curves of the interfacial stress intensity factor (K) vs. normalized radial distance (R/a), are obtained through numerical simulations coupled with thin film fracture mechanics relations. Results from experimental studies on an exposed EB-PVD TBC specimen are presented. The goal of this work is to obtain larger debond sizes for high toughness specimens and smaller debond sizes for low toughness specimens, while maintaining an adequate indentation depth.
3
ZHUANG, LINQI, LUCIO MARAGONI, and RAMESH TALREJA. "EFFECT OF MICROSTRUCTURE ON INITIATION OF DELAMINATION IN CROSS PLY LAMINATES FROM A TRANSVERSE CRACK." In Thirty-sixth Technical Conference. Destech Publications, Inc., 2021. http://dx.doi.org/10.12783/asc36/35848.
Анотація:
Transverse crack propagating towards a cross-ply interface is investigated in this study. The non-uniform fiber distribution near ply interface is modelled explicitly in order to study the effect of microstructure on crack path and initiation of delamination. The growth of fiber/matrix interfacial debond and debond kinking out of interface are analyzed based on a combination of energy and stress-based approach, which is convenient in predicting matrix crack path. Kinking of transverse crack tip when it approaches ply interface is investigated using an energy-based approach. It is found that predicted matrix crack path and crack tip kinking behavior near interface is strongly influenced by the local microstructure. The obtained results indicate that an induced symmetrical delamination, i.e., interface cracks of equal length on either side of the transverse ply crack, as often assumed in modeling studies, is not always a favorable damage mode.
4
D., Sharath, Ajay Rawat, M. Menaka, B. Venkatraman, and Baldev Raj. "Effect of Air-Gap Thickness on Debond Detection in Coatings using Pulsed Thermography: A Numerical Study." In Quantitative InfraRed Thermography Asia 2015. QIRT Council, 2015. http://dx.doi.org/10.21611/qirt.2015.0142.
5
Wang, Chien-Yu, Tz-Cheng Chiu, Wei-Jie Yin, Dao-Long Chen, Tang-Yuan Chen, and Chin-Li Kao. "A Quantitative Evaluation of the Inelastic Energy Absorptions in Cu-Polyimide Interconnect and the Effect on Interface Debond Driving Force." In 2023 IEEE 73rd Electronic Components and Technology Conference (ECTC). IEEE, 2023. http://dx.doi.org/10.1109/ectc51909.2023.00125.
6
Layne, Andrew M., and Leif A. Carlsson. "Effects of Interfacial Delaminations in Curved Sandwich Beams." In ASME 2000 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2000. http://dx.doi.org/10.1115/imece2000-2030.
Анотація:
Abstract The influence of face/core debonding on the structural integrity of curved sandwich beams subjected to opening bending moments has been examined experimentally. The sandwich beams consisted of glass/polyester faces over a PVC H30 foam core. Debonds of various sizes were implanted by inserting thin teflon sheets at the outer face/core interface in the curved region of the beam prior to processing. A test fixture for flexure testing of curved sandwich beams was designed and manufactured, and evaluated using homogeneous isotropic beams. The surface strains at the middle of the curve were recorded to examine the response. Buckling of the debonded face sheet occurred followed by face/core propagation of the debond. Strength reduction of the beams under opening moments due to face/core debonding was substantial.
7
MITRA, AUROVINDA KUMAR, and DHANASHRI M. JOGLEKAR. "DEBOND LOCALIZATION IN HONEYCOMB CORE SANDWICH COMPOSITES USING A0 GUIDED WAVE MODE." In Structural Health Monitoring 2023. Destech Publications, Inc., 2023. http://dx.doi.org/10.12783/shm2023/36961.
Анотація:
Honeycomb core composite sandwich structures (HCCSSs) are widely employed in the marine, defense, and aerospace industries due to their lightweight design, the superior ratio of strength-to-weight and high load-bearing capabilities. Regardless of such commendable advantages, the skin-core junctions are susceptible to debond damage from intensive loading on these structures that may threaten the safety and structural integrity of the assembly. In this study, a novel framework for the guided wave based non-destructive evaluation (NDE) of a three-dimensional HCCSS is presented. The total focusing method with full matrix capture (TFM-FMC) technique is employed to detect and quantify debond at multiple locations in the finite element model of the three-dimensional HCCSS. The fundamental antisymmetric (A0) mode of guided waves is considered for multiple debond assessments in the investigated structure. The A-scan responses of the propagating guided wave of a debond HCCSS are compared with that of a pristine model. This comparison served as a valuable damage precursor resulting from interaction effects. A substantial amplification of the modal amplitude in the case of debonded HCCSS is noticed compared to that of the pristine model. The A-scan responses captured at a location distant from the debonded zone showed little difference. The TFM-FMC algorithm based structural monitoring framework is utilized to locate and quantify the debonded zones in the HCCSS. The proposed health monitoring framework is considered to be substantially effective in the detection of debond damages in a composite sandwich structure.
8
Snodgrass, J. M., S. Y. Kook, A. Kirtikar, and R. H. Dauskardt. "Adhesion and Reliability of Polymer/Inorganic Interfaces in Microelectronic Applications." In ASME 1997 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 1997. http://dx.doi.org/10.1115/imece1997-0497.
Анотація:
Abstract The reliability of microelectronic components is profoundly influenced by the interfacial fracture resistance (adhesion) and resistance to progressive debonding of interfaces. In this study we examine the interfacial fracture properties of representative polymer interfaces commonly found in microelectronic applications. Specifically, interface fracture mechanics techniques are described to characterize adhesion and progressive debonding behavior of a polymer/metal interface under cyclic fatigue loading. Cyclic fatigue debond-growth rates were measured from ∼10−10 to 10−6 m/cycle and found to display a power-law dependence on the applied strain energy release rate range, ΔG. Fracture toughness test results show that the interfaces typically exhibit resistance-curve behavior, with a plateau interface fracture resistance, Gss, strongly dependent on the interface morphology and the thickness of the polymer layer. The effect of a chemical adhesion promoter on the fracture energy of a polymer/silicon interface was also characterized. Micromechanisms controlling interfacial adhesion and progressive debonding are discussed in terms of the prevailing deformation mechanisms and related to interface structure and morphology.
9
Viana Camps, Gilmer M., Leif A. Carlsson, and Xiaoming Li. "Influence of Core on Face/Core Debond Toughness." In ASME 2000 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2000. http://dx.doi.org/10.1115/imece2000-2026.
Анотація:
Abstract The influence of mechanical properties and fracture toughness of the core on debond fracture toughness of foam core sandwich has been examined. It was found that the fracture toughness for debonding was larger than the core toughness. The observed difference between core fracture toughness and face/core debonding toughness was analyzed using plastic zone size and mode mixity arguments. The difference in toughness can not be explained by plastic zone size and mode mixity effects. It is possible that the core displays a gradient in properties and fracture resistance, and anisotropic behavior which might explain the difference in toughness.
10
DOSHI, SAGAR M., ALEX SCHNEIDER, JOSEPH M. DEITZEL, and JOHN W. GILLESPIE, JR. "INTERFACIAL CHARACTERIZATION OF S2 GLASS-EPOXY RESIN USING SINGLE FIBER PULLOUT TESTS AT VARYING TEMPERATURE AND MOISTURE LEVEL." In Proceedings for the American Society for Composites-Thirty Eighth Technical Conference. Destech Publications, Inc., 2023. http://dx.doi.org/10.12783/asc38/36643.
Анотація:
Due to their high specific strength, stiffness, and energy-absorbing properties, glass fiber epoxy composites are commonly used in automotive, aerospace, and other consumer applications. The Army uses these composites in ground vehicles for various structures, and they are often subjected to a wide range of environmental conditions, with varying temperature and moisture conditions. They may also be subjected to high strain rate loading. While the influence of environmental conditions on the properties of the reinforcing fibers is minimal, a fundamental understanding of its effect on the resin and interfacial adhesion is critical in evaluating the behavior of these composites. This research focuses on characterizing the effect of temperature and moisture on the interfacial bonding between S2 glass fibers (with 463 sizing) and epoxy resin using single fiber pullout testing. Epoxy resin SC-15, commonly used in these applications, is tested at room temperature, -55ºC and 76ºC. The range is chosen based on the operating temperature defined by MIL 810 standards. The embedded length is comparable for all tests, of the order of 55-60 μm. The embedded length and average diameter are measured using a scanning electron microscope image of the failed specimen to calculate the apparent IFSS. The IFSS shows a strong correlation with temperature; an increase in IFSS at -55ºC and a decrease at 76ºC. An 89% increase was measured at -55ºC and a 45% decrease at 76ºC when compared to room temperature tests. The IFSS measured is dependent on various factors such as the surface roughness of the fiber, chemical bonds between the resin and the fiber (sizing), and the residual compression forces that induce friction within debond regions due to the difference in CTE (coefficient of thermal expansion) between the fiber and the resin. Due to competing mechanisms of resin failure or interfacial failure, in some cases, a residue of the resin on the fiber may be present. A discussion of these mechanisms and a comparison with the resin properties at different temperatures is discussed.
Звіти організацій з теми "Debond effect":
1
Kardomateas, George A. Compressive Response of Debonded Thick Composite Shells Including the Effects of Transient Moisture Sorption. Fort Belvoir, VA: Defense Technical Information Center, July 1991. http://dx.doi.org/10.21236/ada250080.