The Experts below are selected from a list of 44532 Experts worldwide ranked by ideXlab platform
Akira Todoroki - One of the best experts on this subject based on the ideXlab platform.
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analysis of electric current density in carbon fiber reinforced plastic laminated plates with angled plies
Composite Structures, 2017Co-Authors: Takuya Yamane, Akira TodorokiAbstract:Abstract It is important to know the electric current distribution in a laminated carbon fiber reinforced plastics (CFRP) plates for safety analysis of lightning strikes and for damage monitoring of plates based on changes in electrical resistance. An orthotropic electric potential function has been previously proposed, which was effective for modeling of a CFRP cross-ply laminate used in beam structures. However, that method is limited to cross-ply Laminates that contain no angle plies, while CFRP plate structures typically feature angle plies. In the present study, a new analysis method is proposed for laminated CFRP plates that contain angled plies. In the new method, two or three angle plies are coupled and assumed to have orthotropic conductivity of double or triple thickness. A new method to calculate the equivalent conductivity is also proposed. The new method is applied to two types of Laminates containing angle ply structures. The results obtained are compared with those from a finite difference method and from experimental measurements. The new method is shown to be effective for analysis of the electric current of Laminates that contain angled plies.
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Through-thickness electric conductivity of toughened carbon-fibre-reinforced polymer Laminates with resin-rich layers
Composites Science and Technology, 2016Co-Authors: Yoshiyasu Hirano, Takuya Yamane, Akira TodorokiAbstract:Self-sensing carbon-fibre-reinforced polymer (CFRP) that use changes in electrical resistance has been applied to monitor delamination cracks in CFRP composite structures. CFRP laminated composites have orthotropic electric conductivity. Despite the existence of insulator resin-rich layers between each ply, the toughened CFRP Laminates have electric conductivity in the thickness direction, which plays important role in delamination monitoring with changes in electrical resistance. Further more, it is also quite important to understand the lightning damage behaviour of CFRP laminate and to perform numerical simulations estimating the current flow in CFRP laminate when lightning event. However, the measured electric conductance has not been confirmed to be a material property for toughened CFRP. The objective of the present study is thus to clarify the mechanism of realizing electric conductivity in the through-thickness direction. During the curing process, alternating current is applied, and impedance is measured for toughened CFRP. It is found that conductivity in the through-thickness direction of toughened CFRP Laminates is due to chance carbon fibre contact between plies during the curing process, and is not a material property.
Takuya Yamane - One of the best experts on this subject based on the ideXlab platform.
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analysis of electric current density in carbon fiber reinforced plastic laminated plates with angled plies
Composite Structures, 2017Co-Authors: Takuya Yamane, Akira TodorokiAbstract:Abstract It is important to know the electric current distribution in a laminated carbon fiber reinforced plastics (CFRP) plates for safety analysis of lightning strikes and for damage monitoring of plates based on changes in electrical resistance. An orthotropic electric potential function has been previously proposed, which was effective for modeling of a CFRP cross-ply laminate used in beam structures. However, that method is limited to cross-ply Laminates that contain no angle plies, while CFRP plate structures typically feature angle plies. In the present study, a new analysis method is proposed for laminated CFRP plates that contain angled plies. In the new method, two or three angle plies are coupled and assumed to have orthotropic conductivity of double or triple thickness. A new method to calculate the equivalent conductivity is also proposed. The new method is applied to two types of Laminates containing angle ply structures. The results obtained are compared with those from a finite difference method and from experimental measurements. The new method is shown to be effective for analysis of the electric current of Laminates that contain angled plies.
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Through-thickness electric conductivity of toughened carbon-fibre-reinforced polymer Laminates with resin-rich layers
Composites Science and Technology, 2016Co-Authors: Yoshiyasu Hirano, Takuya Yamane, Akira TodorokiAbstract:Self-sensing carbon-fibre-reinforced polymer (CFRP) that use changes in electrical resistance has been applied to monitor delamination cracks in CFRP composite structures. CFRP laminated composites have orthotropic electric conductivity. Despite the existence of insulator resin-rich layers between each ply, the toughened CFRP Laminates have electric conductivity in the thickness direction, which plays important role in delamination monitoring with changes in electrical resistance. Further more, it is also quite important to understand the lightning damage behaviour of CFRP laminate and to perform numerical simulations estimating the current flow in CFRP laminate when lightning event. However, the measured electric conductance has not been confirmed to be a material property for toughened CFRP. The objective of the present study is thus to clarify the mechanism of realizing electric conductivity in the through-thickness direction. During the curing process, alternating current is applied, and impedance is measured for toughened CFRP. It is found that conductivity in the through-thickness direction of toughened CFRP Laminates is due to chance carbon fibre contact between plies during the curing process, and is not a material property.
Chenguang Huang - One of the best experts on this subject based on the ideXlab platform.
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interlaminar damage of carbon fiber reinforced polymer composite laminate under continuous wave laser irradiation
Optics and Lasers in Engineering, 2017Co-Authors: Yanchi Liu, Yihui Huang, Hongwei Song, Chenguang HuangAbstract:Abstract The interlaminar damages were investigated on the carbon fiber reinforced polymer (CFRP) composite laminate under laser irradiation. Firstly, the laminated T700/BA9916 composites were exposed to continuous wave laser irradiation. Then, the interface cracking patterns of such composite Laminates were examined by optical microscopy and scanning electron microscopy. Finally, the Finite Element Analysis (FEA) was performed to compute the interface stress of the Laminates under laser irradiation. And the effects of the laser parameters on the interlaminar damage were discussed.
Maria Kashtalyan - One of the best experts on this subject based on the ideXlab platform.
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Stiffness and fracture analysis of laminated composites with off-axis ply matrix cracking
Composites Part A-applied Science and Manufacturing, 2007Co-Authors: Maria KashtalyanAbstract:Matrix cracks parallel to the fibres in the off-axis plies is the first intralaminar damage mode observed in laminated composites subjected to static or fatigue in-plane tensile loading. They reduce laminate stiffness and strength and trigger development of other damage modes, such as delaminations. This paper is concerned with theoretical modelling of unbalanced symmetric Laminates with off-axis ply cracks. Closed-form analytical expressions are derived for Mode I, Mode II and the total strain energy release rates associated with off-axis ply cracking in [0/θ] s Laminates. Stiffness reduction due to matrix cracking is also predicted analytically using the Equivalent Constraint Model (ECM) of the damaged laminate. Dependence of the degraded stiffness properties and strain energy release rates on the crack density and ply orientation angle is examined for glass/epoxy and carbon/epoxy Laminates. Suitability of a mixed mode fracture criterion to predict the cracking onset strain is also discussed.
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application of the boundary shape perturbation method to stress analysis of laminated composites with ply waviness
Composites Part A-applied Science and Manufacturing, 2005Co-Authors: Maria KashtalyanAbstract:Ply waviness is a manufacturing defect that occurs in thick fibre-reinforced composite Laminates during the curing process. It is known to cause significant degradation of mechanical properties and fatigue life, particularly under compressive loading. To predict failure in the vicinity of the wavy layer, accurate information about stresses at the undulating interfaces is needed. In this paper, an analytical approach to determination of stresses in laminated composites with ply waviness subjected to compressive or flexural loading is presented. Using the boundary shape perturbation method, 3D elasticity problem for a laminate with undulating interfaces is transformed into a sequence of 3D elasticity problems for a reference laminate with perfectly flat layers. The application of the presented analytical approach to a particular problem is illustrated with the example of a transversally loaded laminated plate with a wavy layer.
Yuejie Cao - One of the best experts on this subject based on the ideXlab platform.
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experimental investigation on bearing behavior and failure mechanism of double lap thin ply composite bolted joints
Composite Structures, 2021Co-Authors: Yuejie Cao, Zengqiang Cao, Yibao Zhao, Duquan Zuo, Jie Zhi, Guo Zheng, T E TayAbstract:Abstract Thin-ply laminated composites have recently gained increasing attention in the aerospace engineering field, due to enhanced design possibilities and positive size effects with regard to decreasing ply thickness. In this paper, the mechanical behavior of thin-ply laminate and TC21 titanium alloy hybrid joints with double-lap bolted structure under quasi-static loading was studied experimentally. X-ray computed tomography (CT) scanning and SEM microcosmic imaging at special stages of the whole loading process were used to clarify the progression of bearing damage and fastening hole deformation characteristics of Laminates. A more gradual damage and failure in bearing was observed in all specimens from the stress-displacement curves. The final failure of hybrid joints is a combined mode of bolt tensile cracking and hole bearing deformation. More importantly, the common delamination of standard-ply composite laminated plates in the bearing failure plane and tensile failure plane was suppressed in thin-ply Laminates, resulting in higher bearing failure strength and more damage accumulation. Therefore, the novelty of this work contributes to detailed experimental observations of the bearing failure mechanisms, which provide valuable information for developing accurate mechanism-based failure models to be used in simulations.