Thomas H. Hannah, Reuben H. Kraft, V. Martin, S. Ellis
Kolsky Bar systems are subjected to inherent system error as all measurement devices are. This is especially true in that as the bar diameter decreases, the system becomes more sensitive to errors such as friction and misalignment. In this work we present a technique for identifying and quantifying the error of a Kolsky system. We also present a method of generating statistically significant bounds for Kolsky systems so that anomalous or improperly executed experiments can be quantitatively identified. This method does not rely on the intuition of the experimentalist to identify an anomalous experiment. After presenting our method for error identification, a series of tests are performed on 2024Aluminum alloy samples. A method is then presented where the system error, as well as some error contributed by a variance in sample dimension, are removed from the calculated error related to the stress on the samples. The result shows the effective variance of the sample response is quite high in the elastic loading period, but reduces when plasticity dominates. This is attributed to the presence of high frequency content in the travelling elastic waves which cannot be accurately measured currently, but is effectively damped out when plastic deformation dominates.
{"title":"Implications of Statistical Spread to Experimental Analysis in a Novel Miniature Kolsky Bar","authors":"Thomas H. Hannah, Reuben H. Kraft, V. Martin, S. Ellis","doi":"10.1115/IMECE2020-23976","DOIUrl":"https://doi.org/10.1115/IMECE2020-23976","url":null,"abstract":"\u0000 Kolsky Bar systems are subjected to inherent system error as all measurement devices are. This is especially true in that as the bar diameter decreases, the system becomes more sensitive to errors such as friction and misalignment. In this work we present a technique for identifying and quantifying the error of a Kolsky system. We also present a method of generating statistically significant bounds for Kolsky systems so that anomalous or improperly executed experiments can be quantitatively identified. This method does not rely on the intuition of the experimentalist to identify an anomalous experiment. After presenting our method for error identification, a series of tests are performed on 2024Aluminum alloy samples. A method is then presented where the system error, as well as some error contributed by a variance in sample dimension, are removed from the calculated error related to the stress on the samples. The result shows the effective variance of the sample response is quite high in the elastic loading period, but reduces when plasticity dominates. This is attributed to the presence of high frequency content in the travelling elastic waves which cannot be accurately measured currently, but is effectively damped out when plastic deformation dominates.","PeriodicalId":23837,"journal":{"name":"Volume 3: Advanced Materials: Design, Processing, Characterization, and Applications","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-11-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79816452","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}
Elevated temperature performance of advanced conductors are investigated with a one-dimensional joule heating model. Step-by-step development and validation of the ampacity prediction model are discussed and results from case studies are provided. A potential advantage of advanced electrical conductors is their relatively low density. Copper — as reference — is compared with carbon-based conductors and copper nanocomposites, on the basis of equivalent volume and equivalent weight. It is shown that while doped carbon nanotube (CNT) conductors may potentially result in an improved conductor compared with copper on a weight basis, ultra-conductive copper (UCC) can outperform copper on both volume and weight bases.
{"title":"Numerical Simulation of Ampacity in Advanced Electrical Conductors","authors":"Pouria Khanbolouki, M. Tehrani","doi":"10.1115/IMECE2020-23698","DOIUrl":"https://doi.org/10.1115/IMECE2020-23698","url":null,"abstract":"\u0000 Elevated temperature performance of advanced conductors are investigated with a one-dimensional joule heating model. Step-by-step development and validation of the ampacity prediction model are discussed and results from case studies are provided. A potential advantage of advanced electrical conductors is their relatively low density. Copper — as reference — is compared with carbon-based conductors and copper nanocomposites, on the basis of equivalent volume and equivalent weight. It is shown that while doped carbon nanotube (CNT) conductors may potentially result in an improved conductor compared with copper on a weight basis, ultra-conductive copper (UCC) can outperform copper on both volume and weight bases.","PeriodicalId":23837,"journal":{"name":"Volume 3: Advanced Materials: Design, Processing, Characterization, and Applications","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-11-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82569685","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}
P. Araújo, J. Teixeira, Dionísio Silveira, Elisabete Silva, D. Soares, R. Fangueiro, M. Vilarinho
The protection of human life and goods assumes a growing concern in all forms of activities. The fire and smoke curtains have as main role to act as a physical barrier to prevent the fire from spreading between spaces as well as to staunch the smoke and heat transfer to adjacent areas. They can also be easily operated (opening and closing) causing a minimal interference with the flow of materials and humans within confines spaces, such as warehouses and industries, while providing adequate protection. Thus, there are a set of characteristics that these products must exhibit high fire protection, thermal resistance and gas impermeability. The classification of the heat resistance, described in the European Standard BS EN 1634-1: Fire resistance and smoke control tests for door, shutter and, openable window assemblies and elements of building hardware — fire resistance tests for doors, shutters and openable windows, is the procedure that allows determining the response of a product in contributing by its decomposition to a fire to which it is exposed, being according to three criteria: (i) integrity, (ii) insulation and (iii) radiation. Usually curtains are based on fiber-based structures which can be coated to enhance their protective capabilities. In addition, the fibrous structure can be tailored to optimize its behaviour using 2D and 3D complex architectures, with single or multiple materials. The performance assessment of the curtains regarding the aforementioned parameters is performed resorting to several experimental procedures that are detailed in the specific standards. The present paper reports the development of novel fibrous structures used for heat protection curtains. They are based on the various combinations of hybrid structures combining 2 or 3 different yarn materials. The tests are carried out in a purpose built oven that induces a steep temperature rate (approximately 600 °C in 5 min) on one side of the sample followed by a slower rate up to 950 °C in 60 min. The sample is placed under stress during the test in order to mimic that caused by its own weight. Thermocouples monitor the temperature on both sides of the sample and its integrity is assessed by both the occurrence of fabric rupture and smoke release due to ignition. Both the fabric integrity and the temperature on the back side of the sample are an indicator of its performance which follows the European Standard BS EN 13501-2: Fire classification of construction products and building elements. Classification using data from fire resistance tests, excluding ventilation services. From the results one can conclude that hybrid structures, including either basalt and glass fibers, are the most suitable.
在所有形式的活动中，对人的生命和财产的保护日益受到关注。防火和防烟帘的主要作用是充当物理屏障，防止火灾在空间之间蔓延，并阻止烟雾和热量传递到邻近区域。它们也可以很容易地操作(打开和关闭)，对仓库和工业等有限空间内的物料和人员流动造成最小的干扰，同时提供足够的保护。因此，有一系列的特性，这些产品必须具有高的防火性，耐热性和气体不渗透性。欧洲标准BS EN 1634-1:门、百叶窗和可打开的窗户组件和建筑五金元件的耐火性和烟雾控制测试-门、百叶窗和可打开的窗户的耐火性测试中描述的耐热性分类是允许根据三个标准确定产品通过其分解对其暴露在火灾中的反应的程序:(i)完整性，(ii)绝缘性和(iii)辐射性。窗帘通常是基于纤维结构，可以涂上涂层以增强其防护能力。此外，纤维结构可以使用单一或多种材料定制2D和3D复杂结构，以优化其性能。关于上述参数的窗帘性能评估是通过几个实验程序进行的，具体标准中有详细说明。本文报道了用于防热窗帘的新型纤维结构的发展。它们是基于混合结构的各种组合，结合2或3种不同的纱线材料。测试在特制的烘箱中进行，该烘箱在样品的一侧诱导急剧升温(5分钟内约600°C)，然后在60分钟内缓慢升温至950°C。在测试期间，样品置于应力下，以模拟由其自身重量引起的应力。热电偶监测样品两侧的温度，并通过织物破裂和因着火而释放烟雾的情况来评估其完整性。织物的完整性和样品背面的温度都是其性能的指标，符合欧洲标准BS EN 13501-2:建筑产品和建筑构件的防火分类。使用耐火测试数据进行分类，不包括通风设备。从结果可以得出结论，混合结构，包括玄武岩和玻璃纤维，是最合适的。
{"title":"Development of Fiber Structures for High Performance Heat Resistant Curtains","authors":"P. Araújo, J. Teixeira, Dionísio Silveira, Elisabete Silva, D. Soares, R. Fangueiro, M. Vilarinho","doi":"10.1115/IMECE2020-24016","DOIUrl":"https://doi.org/10.1115/IMECE2020-24016","url":null,"abstract":"\u0000 The protection of human life and goods assumes a growing concern in all forms of activities. The fire and smoke curtains have as main role to act as a physical barrier to prevent the fire from spreading between spaces as well as to staunch the smoke and heat transfer to adjacent areas. They can also be easily operated (opening and closing) causing a minimal interference with the flow of materials and humans within confines spaces, such as warehouses and industries, while providing adequate protection. Thus, there are a set of characteristics that these products must exhibit high fire protection, thermal resistance and gas impermeability.\u0000 The classification of the heat resistance, described in the European Standard BS EN 1634-1: Fire resistance and smoke control tests for door, shutter and, openable window assemblies and elements of building hardware — fire resistance tests for doors, shutters and openable windows, is the procedure that allows determining the response of a product in contributing by its decomposition to a fire to which it is exposed, being according to three criteria: (i) integrity, (ii) insulation and (iii) radiation.\u0000 Usually curtains are based on fiber-based structures which can be coated to enhance their protective capabilities. In addition, the fibrous structure can be tailored to optimize its behaviour using 2D and 3D complex architectures, with single or multiple materials.\u0000 The performance assessment of the curtains regarding the aforementioned parameters is performed resorting to several experimental procedures that are detailed in the specific standards.\u0000 The present paper reports the development of novel fibrous structures used for heat protection curtains. They are based on the various combinations of hybrid structures combining 2 or 3 different yarn materials. The tests are carried out in a purpose built oven that induces a steep temperature rate (approximately 600 °C in 5 min) on one side of the sample followed by a slower rate up to 950 °C in 60 min. The sample is placed under stress during the test in order to mimic that caused by its own weight. Thermocouples monitor the temperature on both sides of the sample and its integrity is assessed by both the occurrence of fabric rupture and smoke release due to ignition. Both the fabric integrity and the temperature on the back side of the sample are an indicator of its performance which follows the European Standard BS EN 13501-2: Fire classification of construction products and building elements. Classification using data from fire resistance tests, excluding ventilation services.\u0000 From the results one can conclude that hybrid structures, including either basalt and glass fibers, are the most suitable.","PeriodicalId":23837,"journal":{"name":"Volume 3: Advanced Materials: Design, Processing, Characterization, and Applications","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-11-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89441757","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}
Thermoplastic composites are highly recommended for structural application, not only for their superior characteristics derived from the fiber and matrix materials but also for their recycling possibilities, which is a major issue in the today’s engineering practice. The manufacturing techniques for thermoplastics are different from those for the well-established thermoset composites. This paper addresses the quality of the thermoplastic composites by assessing the distribution of the fiber, the void contents and the waviness of the fibers, compared to the thermoset composites. IM7/PEEK and AS4/PA12 are the two thermoplastic composite systems used for this study, whereas, IM7/8552 is the thermoset composite used as reference. The specimens were examined using optical microscopy and computed tomography (CT) and the results were statistically treated using circular statistics. Compared to the IM7/8552 composite, the analysis reveals that the IM7/PEEK and AS4/PA12 composites, manufactured by ATP result in a higher volume of voids. On the other hand, ATP processing improves the alignment of the fibers, as the solidification process occurs while the fibers are in tension. The microscopy studies also show that the ATP manufactured composites have an area in between the different layers of tape with a low number of fibers, compared to the other areas.
{"title":"On the Manufacturing Defects of Thermoplastic Carbon/Epoxy Composites Manufactured by Automated Tape Placement","authors":"T. Sebaey, N. O’Dowd","doi":"10.1115/IMECE2020-23144","DOIUrl":"https://doi.org/10.1115/IMECE2020-23144","url":null,"abstract":"\u0000 Thermoplastic composites are highly recommended for structural application, not only for their superior characteristics derived from the fiber and matrix materials but also for their recycling possibilities, which is a major issue in the today’s engineering practice. The manufacturing techniques for thermoplastics are different from those for the well-established thermoset composites. This paper addresses the quality of the thermoplastic composites by assessing the distribution of the fiber, the void contents and the waviness of the fibers, compared to the thermoset composites. IM7/PEEK and AS4/PA12 are the two thermoplastic composite systems used for this study, whereas, IM7/8552 is the thermoset composite used as reference. The specimens were examined using optical microscopy and computed tomography (CT) and the results were statistically treated using circular statistics. Compared to the IM7/8552 composite, the analysis reveals that the IM7/PEEK and AS4/PA12 composites, manufactured by ATP result in a higher volume of voids. On the other hand, ATP processing improves the alignment of the fibers, as the solidification process occurs while the fibers are in tension. The microscopy studies also show that the ATP manufactured composites have an area in between the different layers of tape with a low number of fibers, compared to the other areas.","PeriodicalId":23837,"journal":{"name":"Volume 3: Advanced Materials: Design, Processing, Characterization, and Applications","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-11-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73951558","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}
In order to allow for the numerical modeling of impacts for the design of live fire facilities commonly used by military and law enforcement personnel against next generation and environmentally friendly ammunition currently in development, constitutive models for novel target materials must be developed. Many existing facilities are constructed from AR500 steel, coupled with a layer of cellular rubber to reduce impact velocities and contain projectile fragments. High strain rate models, such as the commonly used Johnson-Cook constitutive model, are widely available to characterize AR500 steel, but calibrated models do not currently exist to characterize the cellular rubber. This project seeks to address this shortfall and provide a suitable material model for designers of these facilities in order to ensure the safety of users and the public. Appropriate constitutive models that account for the large strain, high strain rates, and temperature effects experienced during ballistic events and the porosity of the material were researched and a plan developed for future materials testing. Three suitable models were selected for further analysis — A Non-Linear Elastic Model described by Johnson in his work with polyurethane coupled with a Mie-Gruneisen equation of state to account for the porosity of the material, an Osborn-Hull model developed for use with crushable solids, and the Holmquist-Johnson-Cook Model commonly used for cementitious materials.
{"title":"Initial Testing and Constitutive Modeling of Cellular Rubber Subjected to Large Strains and High Strain Rates","authors":"James A. Bieler, B. Davis","doi":"10.1115/IMECE2020-23866","DOIUrl":"https://doi.org/10.1115/IMECE2020-23866","url":null,"abstract":"\u0000 In order to allow for the numerical modeling of impacts for the design of live fire facilities commonly used by military and law enforcement personnel against next generation and environmentally friendly ammunition currently in development, constitutive models for novel target materials must be developed. Many existing facilities are constructed from AR500 steel, coupled with a layer of cellular rubber to reduce impact velocities and contain projectile fragments. High strain rate models, such as the commonly used Johnson-Cook constitutive model, are widely available to characterize AR500 steel, but calibrated models do not currently exist to characterize the cellular rubber. This project seeks to address this shortfall and provide a suitable material model for designers of these facilities in order to ensure the safety of users and the public. Appropriate constitutive models that account for the large strain, high strain rates, and temperature effects experienced during ballistic events and the porosity of the material were researched and a plan developed for future materials testing. Three suitable models were selected for further analysis — A Non-Linear Elastic Model described by Johnson in his work with polyurethane coupled with a Mie-Gruneisen equation of state to account for the porosity of the material, an Osborn-Hull model developed for use with crushable solids, and the Holmquist-Johnson-Cook Model commonly used for cementitious materials.","PeriodicalId":23837,"journal":{"name":"Volume 3: Advanced Materials: Design, Processing, Characterization, and Applications","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-11-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77708741","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}
M. Mahmoudi, Scott Burlison, S. Moreno, Majid Minary
Polymer derived ceramics (PDC’s) offer a unique opportunity to 3D-print ceramics; however, 3D printing of such polymers require it to be combined with specialized light-sensitive agents and layer-by-layer crosslinking using an optical beam due to their low viscosity. Here, three-dimensional printing of ceramics enabled by dispensing the preceramic polymer from a nozzle inside a yield stress fluid is being demonstrated. The printed parts are crosslinked in the same gel. After crosslinking process, the printed parts are taken out of the gel and prepared for high temperature pyrolysis process that converts the cured parts to ceramic. The specially designed gel was three orders of magnitude more viscous than the preceramic polymer at no shear, which provided a stable medium during the whole process for maintaining the shape of the printed material and prevented possible instabilities. The SEM images of the cross section of the specimens showed that the printed material was dense and without any apparent porosity or cracks. Statistical analysis on the mechanical properties of the printed preceramic polymer specimens revealed that the printed specimens had characteristic strength (∼257 MPa).
{"title":"Freeform 3D-Printing of Pure Ceramics","authors":"M. Mahmoudi, Scott Burlison, S. Moreno, Majid Minary","doi":"10.1115/IMECE2020-23429","DOIUrl":"https://doi.org/10.1115/IMECE2020-23429","url":null,"abstract":"\u0000 Polymer derived ceramics (PDC’s) offer a unique opportunity to 3D-print ceramics; however, 3D printing of such polymers require it to be combined with specialized light-sensitive agents and layer-by-layer crosslinking using an optical beam due to their low viscosity. Here, three-dimensional printing of ceramics enabled by dispensing the preceramic polymer from a nozzle inside a yield stress fluid is being demonstrated. The printed parts are crosslinked in the same gel. After crosslinking process, the printed parts are taken out of the gel and prepared for high temperature pyrolysis process that converts the cured parts to ceramic. The specially designed gel was three orders of magnitude more viscous than the preceramic polymer at no shear, which provided a stable medium during the whole process for maintaining the shape of the printed material and prevented possible instabilities. The SEM images of the cross section of the specimens showed that the printed material was dense and without any apparent porosity or cracks. Statistical analysis on the mechanical properties of the printed preceramic polymer specimens revealed that the printed specimens had characteristic strength (∼257 MPa).","PeriodicalId":23837,"journal":{"name":"Volume 3: Advanced Materials: Design, Processing, Characterization, and Applications","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-11-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89900598","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}
Kostiantyn Vasylevskyi, K. Miroshnichenko, Stanislav Buklovskyi, I. Tsukrov, Hannah Grover, D. V. Citters
Ultra high molecular weight polyethylene (UHMWPE) is widely used in biomedical applications, e.g. as a bearing surface in total joint arthroplasty. Recently, equal channel angular extrusion (ECAE) was proposed as a processing method to achieve higher molecular entanglement and superior mechanical properties of this material. Numerical modeling can be utilized to evaluate the influence of such important manufacturing parameters as the extrusion rate, temperature, geometry of the die, back pressure and friction effects in the ECAE of polyethylenes. In this paper we focus on the development of efficient FE models of ECAE for UHMWPE. We study the applicability of the available constitutive models traditionally used in polymer mechanics for UHMWPE, evaluate the importance of the proper choice of the friction parameters between the billet and the die, and compare the accuracy of predictions between 2D (plane strain) and 3D models. Our studies demonstrate that the choice of the constitutive model is extremely important for the accuracy of numerical modeling predictions. It is also shown that the friction coefficient significantly influences the punch force and that 2D plane strain assumption can become inaccurate in the presence of friction between the billet and the extrusion channel.
{"title":"On Numerical Modeling of Equal Channel Angular Extrusion of Ultra High Molecular Weight Polyethylene","authors":"Kostiantyn Vasylevskyi, K. Miroshnichenko, Stanislav Buklovskyi, I. Tsukrov, Hannah Grover, D. V. Citters","doi":"10.1115/IMECE2020-24111","DOIUrl":"https://doi.org/10.1115/IMECE2020-24111","url":null,"abstract":"\u0000 Ultra high molecular weight polyethylene (UHMWPE) is widely used in biomedical applications, e.g. as a bearing surface in total joint arthroplasty. Recently, equal channel angular extrusion (ECAE) was proposed as a processing method to achieve higher molecular entanglement and superior mechanical properties of this material. Numerical modeling can be utilized to evaluate the influence of such important manufacturing parameters as the extrusion rate, temperature, geometry of the die, back pressure and friction effects in the ECAE of polyethylenes.\u0000 In this paper we focus on the development of efficient FE models of ECAE for UHMWPE. We study the applicability of the available constitutive models traditionally used in polymer mechanics for UHMWPE, evaluate the importance of the proper choice of the friction parameters between the billet and the die, and compare the accuracy of predictions between 2D (plane strain) and 3D models.\u0000 Our studies demonstrate that the choice of the constitutive model is extremely important for the accuracy of numerical modeling predictions. It is also shown that the friction coefficient significantly influences the punch force and that 2D plane strain assumption can become inaccurate in the presence of friction between the billet and the extrusion channel.","PeriodicalId":23837,"journal":{"name":"Volume 3: Advanced Materials: Design, Processing, Characterization, and Applications","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-11-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76913148","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}
This research details the process and methodology deployed to better understand the arrangement of colloidal carbon black (CB) nanoparticles in a spray-layer-by-layer (SLBL) manufactured conductive polymer composite (CPC). The effects of various SLBL parameters on the qualitative consistency and electromechanical performance of the resulting sensors are experimentally examined. Microscopy techniques are used to investigate the distribution and resulting CB structures of CPC films deposited on different types of substrates. Various substrate preparation methods and effects are discussed. Electrical characteristics of CPC films are investigated via deposition between copper electrode pairs on printed circuit boards. Practical applications of the characterized films are discussed along with future works regarding such sensors.
{"title":"Development of Manufacturing and Characterization Methods for Carbon Black-Based Conductive Polymer Composite Sensors","authors":"Tyler B. Albright, J. Hobeck","doi":"10.1115/IMECE2020-24060","DOIUrl":"https://doi.org/10.1115/IMECE2020-24060","url":null,"abstract":"\u0000 This research details the process and methodology deployed to better understand the arrangement of colloidal carbon black (CB) nanoparticles in a spray-layer-by-layer (SLBL) manufactured conductive polymer composite (CPC). The effects of various SLBL parameters on the qualitative consistency and electromechanical performance of the resulting sensors are experimentally examined. Microscopy techniques are used to investigate the distribution and resulting CB structures of CPC films deposited on different types of substrates. Various substrate preparation methods and effects are discussed. Electrical characteristics of CPC films are investigated via deposition between copper electrode pairs on printed circuit boards. Practical applications of the characterized films are discussed along with future works regarding such sensors.","PeriodicalId":23837,"journal":{"name":"Volume 3: Advanced Materials: Design, Processing, Characterization, and Applications","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-11-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75615369","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}
Yucheng Yang, F. Fabian, J. McKenzie, Kristyna Hyblova, Q. Ma
Literature has shown that cellulose nanocrystals (CNCs) which are produced through hydrochloric (HCl) acid hydrolysis catalyzed by inorganic chlorides can enhance the mechanical properties of organic polymers further than CNCs by pure HCl acid hydrolysis. The results have shown that the level of reinforcement may be negatively correlated to the dissociation constant of the inorganic chlorides. However, titanium tetrachloride’s dissociation constant is 1.3, lower than that of ferric chloride, 2.2, which is the lowest dissociation constant among the four inorganic chlorides that have been studied. Therefore, for this study, titanium tetrachloride was investigated along with ferric chloride. The only two variables in this study are reaction time and acid-to-microcellulose crystals (MCCs) ratio. The results of laser diffraction spectroscopy (LDS) show that the resultant solutions exhibit binomial size distributions which contain both MCCs and CNCs. At acid-to-MCCs ratio of 40 for ferric chloride, any increase in reaction time above 1.5 hours did not result in size reduction. The Fourier transform infrared (FTIR) spectroscopy results of CNCs showed that the catalyzed hydrolysis did not change the molecular structure of MCCs. The color of CNCs varies with increasing reaction time, but, based on the FTIR and LDS results, the color is not an indication of CNCs’ size nor their chemical composition.
{"title":"The Size Distribution of Cellulose Nanocrystals in the Variation of Acid-to-Microcellulose Crystals Ratio and Reaction Time Through Catalyzed Acid Hydrolysis","authors":"Yucheng Yang, F. Fabian, J. McKenzie, Kristyna Hyblova, Q. Ma","doi":"10.1115/IMECE2020-23653","DOIUrl":"https://doi.org/10.1115/IMECE2020-23653","url":null,"abstract":"\u0000 Literature has shown that cellulose nanocrystals (CNCs) which are produced through hydrochloric (HCl) acid hydrolysis catalyzed by inorganic chlorides can enhance the mechanical properties of organic polymers further than CNCs by pure HCl acid hydrolysis. The results have shown that the level of reinforcement may be negatively correlated to the dissociation constant of the inorganic chlorides. However, titanium tetrachloride’s dissociation constant is 1.3, lower than that of ferric chloride, 2.2, which is the lowest dissociation constant among the four inorganic chlorides that have been studied. Therefore, for this study, titanium tetrachloride was investigated along with ferric chloride. The only two variables in this study are reaction time and acid-to-microcellulose crystals (MCCs) ratio. The results of laser diffraction spectroscopy (LDS) show that the resultant solutions exhibit binomial size distributions which contain both MCCs and CNCs. At acid-to-MCCs ratio of 40 for ferric chloride, any increase in reaction time above 1.5 hours did not result in size reduction. The Fourier transform infrared (FTIR) spectroscopy results of CNCs showed that the catalyzed hydrolysis did not change the molecular structure of MCCs. The color of CNCs varies with increasing reaction time, but, based on the FTIR and LDS results, the color is not an indication of CNCs’ size nor their chemical composition.","PeriodicalId":23837,"journal":{"name":"Volume 3: Advanced Materials: Design, Processing, Characterization, and Applications","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-11-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75223704","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}
Improving the efficiency of the cooling medium to increase productivity and decrease energy consumption is one of the biggest challenges in the current world. Industries, including transportation, manufacturing, and electronic devices, etc. need efficient thermal management and can benefit from the use of efficient cooling media. Industrial coolants i.e. water, ethylene glycol (EG), or mineral oils have long been used for heat transport though the low thermal conductivity (TC) of these coolants has made them inefficient options for high-performance operations. Metal nanofluids can be potential candidates to replace these inefficient coolants because of their superior thermal properties such as high thermal conductivity, diffusivity, and heat transfer coefficient compared to the base fluids. Nanofluids are a stable suspension of nanoparticles in base media which can offer better thermal conductivity and efficiency. However, preparing stable suspension is one of the major challenges of preparing nanofluids as nanoparticles can aggregate faster over time because of their high surface energy which in turn can have an adverse effect on thermal properties. So far, most research investigations have been done on 0-D nanofluids whereas 1-D nanostructure-based nanofluid study is still very limited. In this work, we have developed a suitable route to prepare novel water-based Cobalt nanowire nanofluids and studied their thermal conductivities. Our study shows that the prepared nanofluid is stable and the thermal conductivity is increased by up to 8.5% compared to base fluid (water).
{"title":"Heat Transfer Characteristics of 1-D Ferromagnetic Nanofluid","authors":"Ali Imran Shiave, R. Mohan","doi":"10.1115/IMECE2020-23931","DOIUrl":"https://doi.org/10.1115/IMECE2020-23931","url":null,"abstract":"\u0000 Improving the efficiency of the cooling medium to increase productivity and decrease energy consumption is one of the biggest challenges in the current world. Industries, including transportation, manufacturing, and electronic devices, etc. need efficient thermal management and can benefit from the use of efficient cooling media. Industrial coolants i.e. water, ethylene glycol (EG), or mineral oils have long been used for heat transport though the low thermal conductivity (TC) of these coolants has made them inefficient options for high-performance operations. Metal nanofluids can be potential candidates to replace these inefficient coolants because of their superior thermal properties such as high thermal conductivity, diffusivity, and heat transfer coefficient compared to the base fluids. Nanofluids are a stable suspension of nanoparticles in base media which can offer better thermal conductivity and efficiency. However, preparing stable suspension is one of the major challenges of preparing nanofluids as nanoparticles can aggregate faster over time because of their high surface energy which in turn can have an adverse effect on thermal properties. So far, most research investigations have been done on 0-D nanofluids whereas 1-D nanostructure-based nanofluid study is still very limited. In this work, we have developed a suitable route to prepare novel water-based Cobalt nanowire nanofluids and studied their thermal conductivities. Our study shows that the prepared nanofluid is stable and the thermal conductivity is increased by up to 8.5% compared to base fluid (water).","PeriodicalId":23837,"journal":{"name":"Volume 3: Advanced Materials: Design, Processing, Characterization, and Applications","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-11-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83668085","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}
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