{"title":"Thermal Failure of Composites under Heat Flow","authors":"S. Nomura, B. Karimi","doi":"10.12783/asc33/26051","DOIUrl":"https://doi.org/10.12783/asc33/26051","url":null,"abstract":"","PeriodicalId":337735,"journal":{"name":"American Society for Composites 2018","volume":"100 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-11-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132470054","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}
Achieving reliable means for failure prediction in composites is a standing challenge. To this end, an integrated approach for the diagnosis and prognosis of composites is underscored. It encompasses three key elements. The first is nondestructive inspection enabling 3D measurement of defect size, location and geometry coupled with an automated transition capability to finite element models. The second is accurate and cost effective 3D material property measurements with a minimum number of tests and methods. Finally, achieving structural strength and fatigue life prognosis results from combining the prior elements into comprehensive methods that would ultimately allow for capturing the failure mechanisms associated with multiple damage modes and their interaction. Future research directions emphasize the development of composites processing simulation tools to accelerate the attainment of quality standards and associated dependable allowables.
{"title":"Progress in Failure: Toward Reliable Failure Predictions in Composites","authors":"E. Armanios, G. Seon, Y. Nikishkov, A. Makeev","doi":"10.12783/ASC33/26096","DOIUrl":"https://doi.org/10.12783/ASC33/26096","url":null,"abstract":"Achieving reliable means for failure prediction in composites is a standing challenge. To this end, an integrated approach for the diagnosis and prognosis of composites is underscored. It encompasses three key elements. The first is nondestructive inspection enabling 3D measurement of defect size, location and geometry coupled with an automated transition capability to finite element models. The second is accurate and cost effective 3D material property measurements with a minimum number of tests and methods. Finally, achieving structural strength and fatigue life prognosis results from combining the prior elements into comprehensive methods that would ultimately allow for capturing the failure mechanisms associated with multiple damage modes and their interaction. Future research directions emphasize the development of composites processing simulation tools to accelerate the attainment of quality standards and associated dependable allowables.","PeriodicalId":337735,"journal":{"name":"American Society for Composites 2018","volume":"34 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-11-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132196583","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}
Alexandre S. Dumon, S. Mueller, P. Luca, A. Trameçon
The lack of maturity of crash simulation of structures made of hybrid materials is a key issue for lightweight engineering in automotive industry. Tailoring local behavior and mixing materials while accounting for this mix and joining problematics in the simulation methodology are required to optimize weight and costs, without the need of a real prototype. Current lightweight vehicle programs use local strengthening of structural body components through hot or warm formed high strength steels joined with spot-welds. New metals or composites parts with new joining techniques are progressively introduced for the next stage of weight saving. Local reinforcement by thermo-plastic composites is also considered to offset costs trade-offs.
{"title":"Multi-Scale Analysis of Joints in Hybrid Metal/Composite Structures in ESI Virtual Performance Solution (VPS)","authors":"Alexandre S. Dumon, S. Mueller, P. Luca, A. Trameçon","doi":"10.12783/ASC33/25982","DOIUrl":"https://doi.org/10.12783/ASC33/25982","url":null,"abstract":"The lack of maturity of crash simulation of structures made of hybrid materials is a key issue for lightweight engineering in automotive industry. Tailoring local behavior and mixing materials while accounting for this mix and joining problematics in the simulation methodology are required to optimize weight and costs, without the need of a real prototype. Current lightweight vehicle programs use local strengthening of structural body components through hot or warm formed high strength steels joined with spot-welds. New metals or composites parts with new joining techniques are progressively introduced for the next stage of weight saving. Local reinforcement by thermo-plastic composites is also considered to offset costs trade-offs.","PeriodicalId":337735,"journal":{"name":"American Society for Composites 2018","volume":"25 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-11-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133762144","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}
V. Varshney, V. Unnikrishnana, Jonghoon Lee, S. Sihn, A. Roy
Creating any workable materials construct for any viable applications using carbon or any other nanotubes would invariable involve dispersion of the nanotube in either twodimensional spatial mesh or three-dimensional volumetric space. These dispersed nanotubes invariably are interconnected via overlap or junctions. It is known that the atomic configuration of these nanotube junctions critically influence the bulk properties (structural, thermal, electrical, dielectric). Thus, it is extremely important to pay a close attention to how optimally these junctions can be formed to attain the desirable properties. In all practical situations, experimentally synthesized junctions (either single CNT junctions or junctions in 2D and 3D CNT network structures) are expected to have random orientation of defect sites (non-hexagonal rings) around the junction. Such random nature of junctions’ topology and defect characteristics is expected to affect their strength and durability as well as have impact on associated mesoscopic and macroscopic properties. In this work, we present a generic framework on creating junctions between CNTs with arbitrary spatial (orientation and degree of overlap) and intrinsic (chirality) specifications, as well as to tune degree of topological defects around the junction via a variety of defect annihilation approaches. Our method makes use of the primal/dual meshing concept where the development and manipulation of the junction nodes occur using a triangular meshes (primal mesh), which is eventually converted to its dual (honeycomb mesh) to render a fully-covalently bonded CNT junction where each carbon atom has 3 bonded neighbors (mimicking sp¬2 hybridization). This design approach offers an opportunity to investigate the effect of topological arrangement of defects around the junction on mechanical, electrical and thermal properties. In addition, this junction design methodology is applied to a CNT-graphene junction and to study the effect of local carbon defects (pentagonal or heptagonal carbon ring versus the hexagonal) on junction strength. It is observed that a symmetrical distribution of carbon ring defects around the CNT-graphene junction yield higher strength that that of irregular defect distribution.
{"title":"Atomistic Design of Carbon Nanotube Junctions of Arbitrary Junction Geometry","authors":"V. Varshney, V. Unnikrishnana, Jonghoon Lee, S. Sihn, A. Roy","doi":"10.12783/asc33/25940","DOIUrl":"https://doi.org/10.12783/asc33/25940","url":null,"abstract":"Creating any workable materials construct for any viable applications using carbon or any other nanotubes would invariable involve dispersion of the nanotube in either twodimensional spatial mesh or three-dimensional volumetric space. These dispersed nanotubes invariably are interconnected via overlap or junctions. It is known that the atomic configuration of these nanotube junctions critically influence the bulk properties (structural, thermal, electrical, dielectric). Thus, it is extremely important to pay a close attention to how optimally these junctions can be formed to attain the desirable properties. In all practical situations, experimentally synthesized junctions (either single CNT junctions or junctions in 2D and 3D CNT network structures) are expected to have random orientation of defect sites (non-hexagonal rings) around the junction. Such random nature of junctions’ topology and defect characteristics is expected to affect their strength and durability as well as have impact on associated mesoscopic and macroscopic properties. In this work, we present a generic framework on creating junctions between CNTs with arbitrary spatial (orientation and degree of overlap) and intrinsic (chirality) specifications, as well as to tune degree of topological defects around the junction via a variety of defect annihilation approaches. Our method makes use of the primal/dual meshing concept where the development and manipulation of the junction nodes occur using a triangular meshes (primal mesh), which is eventually converted to its dual (honeycomb mesh) to render a fully-covalently bonded CNT junction where each carbon atom has 3 bonded neighbors (mimicking sp¬2 hybridization). This design approach offers an opportunity to investigate the effect of topological arrangement of defects around the junction on mechanical, electrical and thermal properties. In addition, this junction design methodology is applied to a CNT-graphene junction and to study the effect of local carbon defects (pentagonal or heptagonal carbon ring versus the hexagonal) on junction strength. It is observed that a symmetrical distribution of carbon ring defects around the CNT-graphene junction yield higher strength that that of irregular defect distribution.","PeriodicalId":337735,"journal":{"name":"American Society for Composites 2018","volume":"24 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-11-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133415283","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}
Compressive strength and failure are a common benchmark to qualify the performance of a composite material for many applications. Standard test procedures typically involve compressive test of unidirectional or quasi-isotropic composites from where the properties are back calculated for a single composite ply to obtain the compressive strength of a ply and the laminate. In many applications, the composite material is under multi-axial stress states. In this paper, the influence of through-the-thickness stress on the compressive behavior is studied, with specific intent of replicating loading conditions seen in a bolted joint. Plane strain model of a laminated composite with explicit modeling of fiber and matrix is used in a layered stack-up with different boundary conditions to study the changes in compressive strength as well as residual (post-peak) strength.
{"title":"Effects of Out of Plane Stress on Progressive Kinking in Internal Zero Plies","authors":"P. Davidson, A. Waas","doi":"10.12783/ASC33/25980","DOIUrl":"https://doi.org/10.12783/ASC33/25980","url":null,"abstract":"Compressive strength and failure are a common benchmark to qualify the performance of a composite material for many applications. Standard test procedures typically involve compressive test of unidirectional or quasi-isotropic composites from where the properties are back calculated for a single composite ply to obtain the compressive strength of a ply and the laminate. In many applications, the composite material is under multi-axial stress states. In this paper, the influence of through-the-thickness stress on the compressive behavior is studied, with specific intent of replicating loading conditions seen in a bolted joint. Plane strain model of a laminated composite with explicit modeling of fiber and matrix is used in a layered stack-up with different boundary conditions to study the changes in compressive strength as well as residual (post-peak) strength.","PeriodicalId":337735,"journal":{"name":"American Society for Composites 2018","volume":"7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-11-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132900500","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":"Cycloaliphatic Epoxy -Silica Nanocomposite Provided from Perhydropolysilazane","authors":"R. Saito, T. Sakaguchi, Akio Takasugi","doi":"10.12783/asc33/26083","DOIUrl":"https://doi.org/10.12783/asc33/26083","url":null,"abstract":"","PeriodicalId":337735,"journal":{"name":"American Society for Composites 2018","volume":"101 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-11-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133634610","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}
Melanie Schneider, Pouria Khanbolouki, Nekoda van de Werken, Elijah Wade, R. Foudazi, M. Tehrani
Reducing graphene oxide (GO) is currently seen as one of the most cost effective and scalable methods to produce graphene sheets. This method takes exfoliated graphite in the form of graphene oxide (GO) and reduces it to reduced graphene oxide (rGO). This reduction process recovers the mechanical, thermal, and electrical properties of GO,1 making it more appealing for many applications including fillers in polymers. However, the reduction of oxygen functional groups tends to lead to lower dispersion quality and activity of rGO in polymers. This remains an issue as researchers search to produce graphene based nanocomposites for different applications. This study characterizes the thermal and mechanical properties of graphene oxide and reduced graphene oxide epoxy nanocomposites to determine the overall performance in relation to dispersion quality and nanoparticle loading. For this purpose, epoxy nanocomposites of GO (C:O ratio 1:1) and rGO (C:O ratio 5:1) with various loadings (0.5, 1.0, and 2.0 wt.%) and dispersion qualities (3 different combinations of shear mixing and horn sonication) were fabricated and characterized. Transmission optical microscopy (TOM) and scanning electron microscopy (SEM) were used to qualitatively asses the level of dispersion for each dispersion technique. Flash diffusivity analysis and differential scanning calorimetry (DSC) were employed to measure the thermal diffusivity and specific heat capacity, respectively, for each sample, from which the thermal conductivity was calculated. The thermal conductivity was then correlated to the level of dispersion and filler (GO or rGO) for the composites. Nanoindentation was utilized to assess the mechanical properties of the nanocomposites with respect to dispersion, loading, and filler type.
{"title":"Dispersion and Properties of Graphene Oxide and Reduced Graphene Oxide in Nanocomposites","authors":"Melanie Schneider, Pouria Khanbolouki, Nekoda van de Werken, Elijah Wade, R. Foudazi, M. Tehrani","doi":"10.12783/ASC33/26082","DOIUrl":"https://doi.org/10.12783/ASC33/26082","url":null,"abstract":"Reducing graphene oxide (GO) is currently seen as one of the most cost effective and scalable methods to produce graphene sheets. This method takes exfoliated graphite in the form of graphene oxide (GO) and reduces it to reduced graphene oxide (rGO). This reduction process recovers the mechanical, thermal, and electrical properties of GO,1 making it more appealing for many applications including fillers in polymers. However, the reduction of oxygen functional groups tends to lead to lower dispersion quality and activity of rGO in polymers. This remains an issue as researchers search to produce graphene based nanocomposites for different applications. This study characterizes the thermal and mechanical properties of graphene oxide and reduced graphene oxide epoxy nanocomposites to determine the overall performance in relation to dispersion quality and nanoparticle loading. For this purpose, epoxy nanocomposites of GO (C:O ratio 1:1) and rGO (C:O ratio 5:1) with various loadings (0.5, 1.0, and 2.0 wt.%) and dispersion qualities (3 different combinations of shear mixing and horn sonication) were fabricated and characterized. Transmission optical microscopy (TOM) and scanning electron microscopy (SEM) were used to qualitatively asses the level of dispersion for each dispersion technique. Flash diffusivity analysis and differential scanning calorimetry (DSC) were employed to measure the thermal diffusivity and specific heat capacity, respectively, for each sample, from which the thermal conductivity was calculated. The thermal conductivity was then correlated to the level of dispersion and filler (GO or rGO) for the composites. Nanoindentation was utilized to assess the mechanical properties of the nanocomposites with respect to dispersion, loading, and filler type.","PeriodicalId":337735,"journal":{"name":"American Society for Composites 2018","volume":"9 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-11-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114162939","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}
Xiaodong Cui, A. Karuppiah, D. Pham, J. Lua, C. Saathoff, W. Seneviratne
{"title":"Progressive Damage and Failure Prediction of Interlaminar Tensile Specimen with Initial Fabrication Induced Defects","authors":"Xiaodong Cui, A. Karuppiah, D. Pham, J. Lua, C. Saathoff, W. Seneviratne","doi":"10.12783/ASC33/26089","DOIUrl":"https://doi.org/10.12783/ASC33/26089","url":null,"abstract":"","PeriodicalId":337735,"journal":{"name":"American Society for Composites 2018","volume":"16 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-11-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122139479","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":"Compressive Strength Prediction of 3D Woven Textile Composites: Single RVE Multiscale Analysis and Imperfection Sensitivity Study","authors":"D. Patel, A. Waas","doi":"10.12783/ASC33/26103","DOIUrl":"https://doi.org/10.12783/ASC33/26103","url":null,"abstract":"","PeriodicalId":337735,"journal":{"name":"American Society for Composites 2018","volume":"256 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-11-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121244853","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}
S. Chowdhury, Ethan A. Wise, R. Elder, T. Sirk, D. Hartman, John Gillespie
{"title":"Molecular Dynamics Simulations of Fiber-Sizing Interphase","authors":"S. Chowdhury, Ethan A. Wise, R. Elder, T. Sirk, D. Hartman, John Gillespie","doi":"10.12783/asc33/25917","DOIUrl":"https://doi.org/10.12783/asc33/25917","url":null,"abstract":"","PeriodicalId":337735,"journal":{"name":"American Society for Composites 2018","volume":"7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-11-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116467135","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}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：