Poly(o-toluidine) for carbon fabric electrode modification to enhance the electrochemical capacitance and conductivity

Carbon fabric/phenolic composites modified with potassium titanate whisker (PTW) were prepared by a dip-coating and hot-press molding technique, and the tribological properties of the resulting composites were investigated systematically using a ring-on-block arrangement under different sliding conditions. Experimental results showed that the optimal PTW significantly decreased the wear-rate. The worn surfaces of the composites and the transfer film formed on the counterpart steel ring were examined by scanning electron microscopy (SEM) to reveal the wear mechanisms. The transfer films formed on the counterpart surfaces made contributions to the improvement of the tribological behavior of the carbon fabric composites. The friction and wear of the filled carbon fabric composites was significantly dependent on the sliding conditions. It is observed that the wear-rate increased with increasing applied load and sliding speeds.

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A Novel Composite with Structural Health Monitoring Functionality via 2D and 3D Impedance Mapping Topography

Applied Sciences ◽

10.3390/app11041647 ◽

2021 ◽

Vol 11 (4) ◽

pp. 1647

Author(s):

Georgios Foteinidis ◽

Alkiviadis S. Paipetis

Keyword(s):

Structural Health Monitoring ◽

Health Monitoring ◽

Structural Integrity ◽

Carbon Fabric ◽

Structural Health ◽

The Matrix ◽

Junction Points ◽

Sinusoidal Electric Field ◽

Multi Walled Carbon Nanotubes ◽

Walled Carbon Nanotubes

We report the transformation of a conventional composite material into a multifunctional structure able to provide information about its structural integrity. A purposely positioned grid of carbon fabric strips located within a glass fibre laminate in alternating 0/90 configuration combined with a ternary nanomodified epoxy matrix imparted structural health monitoring (SHM) topographic capabilities to the composite using the impedance spectroscopy (IS) technique. The matrix was reinforced with homogenously dispersed multi-walled carbon nanotubes (MWCNTs) and carbon black (CB). A sinusoidal electric field was applied locally over a frequency range from 1 Hz to 100 kHz between the junction points of the grid of carbon fabric strips. The proposed design enabled topographic damage assessment after a high-velocity impact via the local monitoring of the impedance. The data obtained from the IS measurements were depicted by magnitude and phase delay Bode plots and Nyquist plots. The impedance values were used to create a 2D and a multi-layer (3D) contour topographical image of the damaged area, which revealed crucial information about the structural integrity of the composite.

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Insights into the mechanism, performance and electrode modification of BES-AD combined systems for refractory wastewater treatment: A review

Journal of Water Process Engineering ◽

10.1016/j.jwpe.2020.101895 ◽

2021 ◽

Vol 40 ◽

pp. 101895

Author(s):

Jiawei Xie ◽

Yaofeng Chang ◽

Junxiang Xie ◽

Mabruk Adams ◽

Danqing Zhao ◽

...

Keyword(s):

Wastewater Treatment ◽

Electrode Modification

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Experimental study on the behavior of carbon-fabric reinforced cementitious matrix composites in impressed current cathodic protection

Construction and Building Materials ◽

10.1016/j.conbuildmat.2020.120655 ◽

2020 ◽

Vol 264 ◽

pp. 120655

Author(s):

Ran Feng ◽

Jingzhou Zhang ◽

Ji-Hua Zhu ◽

Feng Xing

Keyword(s):

Experimental Study ◽

Cathodic Protection ◽

Matrix Composites ◽

Carbon Fabric ◽

Cementitious Matrix ◽

Impressed Current ◽

Fabric Reinforced Cementitious Matrix ◽

Impressed Current Cathodic Protection

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Deformation Behavior and Fracture Patterns of Laminated PEEK- and PI-Based Composites with Various Carbon-Fiber Reinforcement

Polymers ◽

10.3390/polym13142268 ◽

2021 ◽

Vol 13 (14) ◽

pp. 2268

Author(s):

Pavel V Kosmachev ◽

Vladislav O Alexenko ◽

Svetlana A Bochkareva ◽

Sergey V Panin

Keyword(s):

Carbon Fiber ◽

Flexural Strength ◽

Laminated Composites ◽

Flexural Modulus ◽

Strength Properties ◽

Fe Model ◽

Carbon Fabric ◽

Model Framework ◽

Order Of Magnitude ◽

Stress States

Laminated composites based on polyetheretherketone (PEEK) and polyimide (PI) matrices were fabricated by hot compression. Reinforcing materials (unidirectional carbon-fiber (CF) tapes or carbon fabric) and their layout patterns were varied. Stress–strain diagrams after three-point flexural tests were analyzed, and both lateral faces of the fractured specimens and fractured surfaces (obtained by optical and scanning electron microscopy, respectively) were studied. It was shown that the laminated composites possessed the maximum mechanical properties (flexural elastic modulus and strength) in the case of the unidirectional CF (0°/0°) layout. These composites were also not subjected to catastrophic failure during the tests. The PEEK-based composites showed twice the flexural strength of the PI-based ones (0.4 and 0.2 GPa, respectively), while the flexural modulus was four times higher (60 and 15 GPa, correspondently). The reason was associated with different melt flowability of the used polymer matrices and varied inter- (intra)layer adhesion levels. The effect of adhesion was additionally studied by computer simulation using a developed two-dimensional FE-model. It considered initial defects between the binder and CF, as well as subsequent delamination and failure under loads. Based on the developed FE-model, the influence of defects and delamination on the strength properties of the composites was shown at different stress states, and the corresponding quantitative estimates were reported. Moreover, another model was developed to determine the three-point flexural properties of the composites reinforced with CF and carbon fabric, taking into account different fiber layouts. It was shown within this model framework that the flexural strength of the studied composites could be increased by an order of magnitude by enhancing the adhesion level (considered through the contact area between CF and the binder).

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