WIT Transactions on State-of-the-art in Science and Engineering最新文献

{"title":"The Model Stirling Engine","authors":"C. König, C. Greated","doi":"10.2495/978-1-84564-149-8/019","DOIUrl":"https://doi.org/10.2495/978-1-84564-149-8/019","url":null,"abstract":"This air engine is exhibited at the Hunterian Museum in Glasgow, Scotland. It was presented in 1827 to Glasgow University by its inventor the Reverend Dr Robert Stirling. The exhibit notes indicate that it is one of only two specimens with the other (a slightly different, earlier model) having been presented to Edinburgh University. Further, the exhibit notes read that ‘it is probable that at least parts of these models were made by Stirling’s brother James, a Dundee-based Iron Master or Founder’. Lord Kelvin claimed to have found this model in an ‘Augean stable’ in 1847. This term is generally used to refer to a messy, dirty and usually crowded or neglected place. The date is contemporary with Kelvin’s adaptation of a cellar situated in the basement of the Old College, High Street, Glasgow, into the world’s first student physical research laboratory. Kelvin subsequently repaired the model and used it in lecture demonstra-tions. The engine runs by using a recurrent cycle of the same trapped air, flowing repeatedly through a connected displacer cylinder (containing a ‘displacer’ plunger) and power piston, with momentum provided by the turn of a flywheel. Air in the large displacer cylinder is heated, rises up past the plunger and flows through a connecting pipe to the piston, causing it to rise and the flywheel to turn. The displacer (plunger) is moved downwards, forcing air into the top of its cylinder. This air cools, due to the presence of a water-filled cooling jacket, situated at the top of the cylinder. The continued momentum of the flywheel causes all the air to move to the top of the cylinder, where it quickly cools. The air is then forced downwards again into the heated part of the cylinder when the piston moves down, pulling the plunger upwards. The air, now in the heated bottom part of the cylinder, expands and increases pressure in the confined displacer cylinder space until it moves past the plunger, through the connector, and into the piston compartment causing the cycle to repeat.","PeriodicalId":336954,"journal":{"name":"WIT Transactions on State-of-the-art in Science and Engineering","volume":"89 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-12-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129799043","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Characterization Of Multifunctional Nanocomposites With Respect To Their Electrical Properties","authors":"H. Estrada, Luke S. Lee","doi":"10.2495/978-1-78466-167-0/021","DOIUrl":"https://doi.org/10.2495/978-1-78466-167-0/021","url":null,"abstract":"Heightened concerns for electromagnetic interference (EMI) in civilian and defence applications have led to the development of multi-functional materials that can provide structural performance while shielding electronic components from electromagnetic waves. Since EMI shielding effectiveness is highly dependent on electrical properties, the goal of this chapter is to present information on how to characterize the conductivity, permittivity and resistivity of nanocomposites; particularly those formed using fiber and carbon nanotube (CNT) reinforced polymer composites. The key components of the nanocomposites are synthetic carbon nanofibers (CNTs). In this chapter, an example will also be provided for a case where the CNTs are embedded in the fiber reinforced material in the form of a non-woven CNT textile, which is proprietary and may be obtained from Nanocomp Technologies Inc. (www.nanocomptech.com). To measure the electrical properties of the nanocomposite, such as conductivity and resistivity, electrical testing of specimens can be conducted using a low frequency impedance analyser. The textile based nanocomposite material’s EMI shielding effectiveness was estimated to be approximately 46 dB for a resistivity of 0.88 ohm/square. Given the material’s average area density of 12.8 g/m 2 , these results can be considered promising since the Nanocomp material can be incorporated into","PeriodicalId":336954,"journal":{"name":"WIT Transactions on State-of-the-art in Science and Engineering","volume":"23 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-12-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129336582","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Development Of The Fabrication Process Of Carbon Nanotube Reinforced Polylactide Acid Nanofiber And Evaluation Of Its Mechanical Properties","authors":"K. Tanaka, M. Hashimoto, M. Nagura, T. Katayama","doi":"10.2495/978-1-78466-167-0/001","DOIUrl":"https://doi.org/10.2495/978-1-78466-167-0/001","url":null,"abstract":"Due to the high surface area to volume ratio, nanofibers are expected to be used for a wide range of applications such as tissue engineering, filter media and reinforcements in composites. The electrospinning technique is a simple method for the fabrication of nanofibers. In this technique, a polymer solution is blown out from a needle hole, while an electric field is applied between a polymer solution and a target. During the electrospinning process, the solvent evaporates and polymer nanofibers are fabricated on the target. To add special functions to nanofibers, functional particle such as calcium carbonate and TiO2 were reported to be used as nano-fillers for nanofibers. Carbon nanotube (CNT), which has excellent mechanical, electrical, chemical resistance and electromagnetic properties, was reported to be reinforcement for bulk polymer resin and CNT is anticipated to be a reinforcing nano-fillers. However, due to challenges such as manipulating extremely small fibers, preparing samples of single-nanofiber and sourcing for accurate and sensitive force transducer, it is difficult to evaluate the mechanical properties of CNT reinforced nanofibers. In this study, CNT/PLA nanofibers were fabricated by the electrospinning method using the electrical potentials difference between two Cu strips of target and the mechanical properties of CNT/PLA nanofiber were evaluated. The morphology of the composite fibers and the dispersion of the CNT within the fibers were observed using transmission electron microscopy (TEM). The tensile test of PLA and CNT/PLA single nanofiber were successfully conducted using a nano-scale tensile testing machine. The tensile strength of PLA and CNT","PeriodicalId":336954,"journal":{"name":"WIT Transactions on State-of-the-art in Science and Engineering","volume":"88 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-12-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130399420","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effect Of Surface Temperature On Tribological Behavior Of Polytetrafluoroethylene Composites","authors":"M. Conte, B. Fernandez, A. Igartua","doi":"10.2495/978-1-78466-167-0/019","DOIUrl":"https://doi.org/10.2495/978-1-78466-167-0/019","url":null,"abstract":"The tribological behavior of polytetrafluoroethylene is highly affected by fillers used to improve its mechanical characteristics and depends on the ability of the material to maintain its integrity under working conditions. Specifically, in the case under study, the heat generated by friction was modelled as a heat flow coming from a source at the contact surface in static condition. Considering that a heat flow is also supplied to the samples during a differential scanning calorimetry analysis, when the crystallinity of the material is evaluated, a correlation between the thermal characteristics of the material, its structure and tribological behavior is presented.","PeriodicalId":336954,"journal":{"name":"WIT Transactions on State-of-the-art in Science and Engineering","volume":"1455 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-12-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132696332","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A Study On Preparation And Mechanical Properties Of Long Jute Fiber Reinforced Polylactic Acid By The Injection Molding Process","authors":"T. Fujiura, K. Sakamoto, Tatsuya Tanaka, Y. Imaida","doi":"10.2495/978-1-78466-167-0/012","DOIUrl":"https://doi.org/10.2495/978-1-78466-167-0/012","url":null,"abstract":"Natural plant fibers have recently attracted attention as reinforcements for plastics due to their high specific mechanical properties and carbon neutrality. This study explored the preparation process for long jute fiber reinforced polylactic acid (LJF/PLA) pellets for injection molding and the mechanical performance of the molded composites. The originally fabricated pultrusion process for manufacturing long fiber reinforced thermoplastic (LFT) was capable of preparing LJF/PLA pellets, with the excellent impregnation of resin into jute fiber bundles. The incorporation of jute fibers of 50 mass% into PLA resulted in the improvement of flexural strength and modulus of injection molded composites. On the other hand, jute reinforcement was not effective for increasing the impact strength of the composite. Moreover, this study also investigated the influence of the moisture that had remained in jute fibers on the mechanical properties of the LJF/PLA composites. As the moisture content of jute fiber increased, the average molecular weight of matrix PLA in the LJF/PLA lowered due to the hydrolysis, and consequently the mechanical properties of the composites decreased. Eliminating moisture from jute fibers in the preparation process of LJF/PLA pellets was found to be important for preventing the deterioration in the molecular weight of PLA and the properties of the molded composites.","PeriodicalId":336954,"journal":{"name":"WIT Transactions on State-of-the-art in Science and Engineering","volume":"56 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-12-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130176016","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Study Of A Continuously Variable Transmission Belt Made Of Carbon Fiber-reinforced Thermoplastic Resin","authors":"T. Minagawa, T. Tanaka, A. Yoshihiko, T. Ichiki, A. Inoue","doi":"10.2495/978-1-78466-167-0/016","DOIUrl":"https://doi.org/10.2495/978-1-78466-167-0/016","url":null,"abstract":"The purpose of this study is to develop automotive frictional parts, especially continuously variable transmission (CVT) blocks using a composite material made of thermoplastic resin and fiber. CVT blocks were used at about 100oC under high pressure and friction conditions; nylon 9T, otherwise named PA9T, was used. PA9T has a high melting point which is higher than the maximum temperature at the state of slip. To apply composite materials to the manufacture of CVT blocks, material properties such as high strength, modulus of elasticity and fatigue strength are important. Therefore, the aim of this study is improvements in mechanical properties by adding fillers to PA9T under various compounding and molding conditions. PA9T and carbon fibers were mixed using a twin screw extruder. After compounding, dumbbell specimens were made using an injection molding machine. Bending, fatigue and abrasion tests were conducted. Moreover, the transmission capacity of CVT belt made of PA9T composites was evaluated and slip tests were conducted. According to the results of tests, PA9T with CF38.8 vol% achieved desired values for CVT application. The CVT belt has a torque capacity of 40 Nm under an axle load of 2.0 kN.","PeriodicalId":336954,"journal":{"name":"WIT Transactions on State-of-the-art in Science and Engineering","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-12-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122985130","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Three-dimensional Molding Of Carbon Fiber Reinforced Thermoplastics By Direct Resistance Heating Of Carbon Fibers","authors":"S. Enoki, K. Moriito, K. Tanaka, T. Katayama","doi":"10.2495/978-1-78466-167-0/008","DOIUrl":"https://doi.org/10.2495/978-1-78466-167-0/008","url":null,"abstract":"To mold carbon fiber reinforced thermoplastics (CFRTP), it is necessary to impregnate carbon fiber bundles with thermoplastic resin by heating the materials. A low cost CFRTP molding technique has been developed in which direct resistance heating is applied to the carbon fiber itself. When an electrical current runs through a material, it is heated by joule heat. Therefore this method can be run with simple equipment and low power consumption. In previous studies by the authors, flat plates and pipes of CFRTP were molded using direct resistance heating and the molding capabilities were evaluated. To use this molding method for manufacturing automobile components, it is necessary to apply it to three-dimensional molding. However, the temperature distribution of carbon fiber non-crimp fabric (NCF) has not been investigated when a direct resistance heating method is applied to three-dimensional molding. In this study, the heating properties of carbon fiber NCF formed by layers at 90o and 120o using direct resistance heating were evaluated, and angle plates were molded. Using direct heating to carbon fiber NCF, angle CF/PA6 plates have been successfully molded under the conditions of holding time of 1 minute, pressure of 2 MPa and heating temperature of 290°C.","PeriodicalId":336954,"journal":{"name":"WIT Transactions on State-of-the-art in Science and Engineering","volume":"88 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-12-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130973793","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Optimization Of Process Parameters For Electrophoretic Deposition In Carbon Nanotubes/carbon Fiber Hybrid Composites","authors":"Y. Q. Wang, J. Byun, B. S. Kim, Jung‐il Song","doi":"10.2495/978-1-78466-167-0/006","DOIUrl":"https://doi.org/10.2495/978-1-78466-167-0/006","url":null,"abstract":"Carbon nanotubes (CNTs) have attracted a great deal of interest in the development of high-performance engineering composites, due to their exceptional physical, mechanical, electronic and thermal properties. Incorporation of CNTs into polymer has resulted in great improvements in functional properties; however, the enhancement of mechanical properties was insignificant compared with that in micro-sized fiber reinforced polymers. In order to realize the application of composites for structural and multifunctional parts, it is necessary to develop hybrid composites with microand nano-sized reinforcements. CNT reinforced hybrid composites have been studied in several ways: the addition of CNTs to a matrix with various dispersion methods, the growth of CNTs on substrate reinforcements, CNT sprays, etc. In this study, the electrophoresis deposition (EPD) method has been applied to deposit CNTs on a carbon fabric. By applying an electric field between a copper plate and a substrate, the negatively charged CNTs in a suspension move toward a carbon fabric. The controllable parameters in the EPD process are identified as the deposition time, the voltage, the contents of the CNTs, and the distance between the copper plate and the carbon fabric. In order to determine the optimal process conditions, the Taguchi method for the statistical design of experiment (DOE) has been utilized. Since the interlaminar shear strength (ILSS) of the hybrid composites is associated with the amount and the degree of distribution of the CNTs, it was selected as the response for the analysis of means and signal-tonoise ratio. The ILSS was measured by short-beam test according to ASTM 2344. The composite sample was fabricated by the vacuum-assisted resin transfer molding process. In addition, the distribution of CNTs was examined by Composites: Advances in Manufacture and Characterisation 53 www.witpress.com, ISSN 1755-8336 (on-line) WIT Transactions on State of the Art in Science and Engineering, Vol 88, © 2015 WIT Press doi:10.2495/978-1-78466-167-0/006 scanning electron microscopy. By utilizing the statistical software MINITAB 14 for DOE, the optimal deposition conditions have been determined.","PeriodicalId":336954,"journal":{"name":"WIT Transactions on State-of-the-art in Science and Engineering","volume":"24 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-12-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130566574","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Moulding of carbon fiber reinforced polycarbonate using unidirectional tapes","authors":"M. Shinohara, S. Isshiki, Y. Fukushima, T. Katayama, K. Tanaka","doi":"10.2495/978-1-78466-167-0/009","DOIUrl":"https://doi.org/10.2495/978-1-78466-167-0/009","url":null,"abstract":"Carbon fiber reinforced plastics (CFRP) are attracting attention in the automotive industry due to their light weight. Thermoset plastics like epoxies are mainly used as matrices of CFRP in that industry. The curing time of the thermosetting resin is long thus leading to poor productivity. Within thermoplastic resins, polycarbonate (PC) is excellent for its impact properties; consequently, it is expected to be used as the matrix of composite materials for automotive structures. Moreover, in order to obtain outstanding strength, the application of continuous fibers as reinforcement is anticipated. However, large-scale equipment is needed and the work of press load is required in order to impregnate PC into continuous fibers. Recently, unidirectional (UD) tapes of CF/PC in which the PC matrix was impregnated into a CF bundle have been developed. In this study, carbon fiber reinforced polycarbonate (CF/PC) was moulded using UD tapes and the practicality of UD tape was examined by studying its mechanical properties aiming at shortening the moulding time.","PeriodicalId":336954,"journal":{"name":"WIT Transactions on State-of-the-art in Science and Engineering","volume":"9 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-12-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114387173","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effect Of Post-cure Conditions On Interfacial Properties Of Glass Fiber/vinylester Composites","authors":"T. Ota, T. Matsuoka","doi":"10.2495/978-1-78466-167-0/011","DOIUrl":"https://doi.org/10.2495/978-1-78466-167-0/011","url":null,"abstract":"Microdroplet tests were carried out in order to investigate the effect of post-cure (PC) conditions on the interfacial properties of glass fiber/vinylester composites. Microdroplet test specimens were postcured at 80°C for a period varying from 4 h to 24 h. The load increased linearly up to the maximum pull-out load, when the load reached the critical load, beyond which the load reduced rapidly under all post-cure conditions. Shear debonding occurred in the fiber/matrix interface at the maximum pull-out load. The maximum load increased with a longer embedded length under all post-cure conditions. In addition, the maximum load was larger with a longer post-cure time. In the cases of PC for 48 h at room temperature plus 8 h and 16 h at 80°C, designated as PC8h and PC16h, respectively, debonding occurred at a short embedded length in contrast to other post-cure conditions. The post-cure conditions PC8h and PC16h improved the interfacial shear strength (IFSS) in comparison with that PC4h. The post-cure condition PC24h decreased the IFSS compared with PC16h. The sizes of the meniscus for both PC8h and PC16h were larger than those for both PC0h and PC4h. The surface of glass fiber was relatively smooth under all post-cure conditions. The residual thermal stress was increased due to post-cure. The mechanical anchoring contributed to the increase in the IFSS.","PeriodicalId":336954,"journal":{"name":"WIT Transactions on State-of-the-art in Science and Engineering","volume":"17 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-12-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123416848","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}