Ballistic efficiency of hybrid laminates based on aramid and UHMWPE prepregs

This contribution focuses on the development of flax and flax/basalt hybrid reinforced composites based on epoxidized linseed oil (ELO) resin, exploiting the feasibility of different ratios of glutaric anhydride (GA) to maleinized linseed oil (MLO) in the hardener system (50:0, 40:10 and 30:20 wt.%) to provide crosslinked thermosets with balanced properties. The hybrid laminates have been manufactured by resin transfer molding (RTM) and subjected to dynamic–mechanical (DMA) and thermal gravimetry (TGA) analysis. The presence of glutaric anhydride (GA) resulted in hard and relatively brittle flax and flax/basalt laminates, whose loss moduli decreased as the number of basalt plies diminished. Furthermore, the increase in MLO content in the GA:MLO hardener system shifted the glass transition temperatures (Tg) from 70 °C to 59 and 56 °C, which is representative of a decrease in brittleness of the crosslinked resin. All samples exhibited two stages of their decomposition process irrespective of the MLO content. The latter influenced the residual mass content that increased with the increase of the MLO wt.% from 10 to 30 wt.%, with shifts of the final degradation temperatures from 410 °C to 425 °C and 445 °C, respectively.

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EFFECTS OF NUMBER OF PLIES ON LIGHTNING STRIKE PROTECTION OF ELECTRICALLY CONDUCTIVE LAYER-WISE HYBRID LAMINATES

10.12783/asc36/35908 ◽

2021 ◽

Author(s):

SIWAT MANOMAISANTIPHAP ◽

TOMOHIRO YOKOZEK YOKOZEKI

Keyword(s):

Epoxy Resin ◽

Composite Laminates ◽

Bending Strength ◽

Fuel Efficiency ◽

Lightning Strike ◽

Conductive Layer ◽

Electrically Conductive ◽

Hybrid Laminates ◽

Conductive Polyaniline ◽

Pani Layer

With the development of composite technologies, aircraft become lighter and more fuel efficiency. The composite aircraft, however, become susceptible to lightning strike. Developing lightning strike protection (LSP) system need to couple with composite technologies. The authors present a concept of LSP using layer-wise hybrid laminates (CF/Hybrid) in this study. The aim of the study is to validate the effectiveness of layer-wise hybrid laminates structure for lightning strike application by using conventional epoxy-resin CFRP for main structure and electrically conductive layer as a cover layer. The composite laminates include two different types of resin in each layer: conductive polyaniline-based matrix (CF/PANI) and conventional epoxy resin (CF/epoxy). CF/PANI layers varied from 1, 2, and 4 layers with corresponding 7, 6, and 4 layers of CF/epoxy to find out the least effective number of CF/PANI that can prevent lightning strike damage. The specimens were characterized for their mechanical properties and underwent simulated lightning strike test to realize their effectiveness. The result of simulated lightning strike has shown that a layer of conductive CF/PANI can help to avoid catastrophic damage on CF/epoxy. With a greater number of CF/PANI, the less detectable damage in CF/PANI layer became. In the case of CF/Hybrid with 4 layers of CF/PANI shows 70% residual bending strength after the lightning strike. With the aid of nondestructive inspection tools, i.e., thermography and ultrasonic test, the mechanism of damage on the composite panels were observed and analyzed. From this study, CF/Hybrid with 4 layers shows the optimal properties for lightning strike protection.

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Investigation of the tensile performance and failure mechanism of carbon–aramid hybrid fibers/epoxy sandwich structure laminates using the UV-thermal synergetic curing mechanism: Experimentation and simulation

Journal of Sandwich Structures & Materials ◽

10.1177/1099636218803416 ◽

2018 ◽

Vol 22 (8) ◽

pp. 2582-2603

Author(s):

Jiaojiao Xi ◽

Xiaoyan Liu ◽

Zhiqiang Yu

Keyword(s):

Finite Element ◽

Failure Mechanism ◽

Sandwich Structure ◽

Experimental Results ◽

Tensile Failure ◽

Hybrid Fibers ◽

Pull Out ◽

Tensile Performance ◽

Hybrid Laminates ◽

Curing Agents

The tensile failure mechanism of carbon–aramid hybrid fibers/epoxy sandwich structure laminates was investigated by using experimental and finite element methods. Double curing agents, triarylsulfonium hexafluoroantimonates and triethylene tetramine with a mass ratio of 4:15 were introduced into the laminates. Sandwich structure laminates, with different proportions of hybrid fibers, were cured by UV-initiated anion/cationic dual curing technique. The results showed that the synergetic curing effects of two curing agents were observed under UV irradiation, leading to the better curing of the system, which further plays a positive influence on the mechanical performance. The tensile properties and failure mechanism of the laminates depended on the stacking sequence and fiber volume fractions of the layer structures. The interplay hybrid laminates, containing three alternate plies with fiber contents of 67.7 vol%, presented the optimal tensile performance, and its tensile strength and modulus were 0.82 GPa and 22.09 GPa, respectively. The fracture morphologies revealed that pull-out and debonding of fibers were the main failure mechanism of hybrid laminates. The performance of sandwich structure laminates was determined by the load-carrying capacity of carbon fiber and load-transferring capacity of the aramid fiber and adhesive. The finite element model based on experiments was established to simulate the stress state and failure mechanism of sandwich laminates. The results demonstrated that the stress was better transferred into carbon fibers from the aramid fibers and adhesive, and the relative error rate of maximum stress from finite element analysis and experimental results was less than 5%, which were in reasonable agreement with the experimental results.

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Hybrid Laminate for Haptic Input Device with Integrated Signal Processing

Applied Sciences ◽

10.3390/app8081261 ◽

2018 ◽

Vol 8 (8) ◽

pp. 1261 ◽

Cited By ~ 2

Author(s):

René Schmidt ◽

Alexander Graf ◽

Ricardo Decker ◽

Verena Kräusel ◽

Wolfram Hardt ◽

...

Keyword(s):

Embedded System ◽

Learning System ◽

Input Device ◽

Full Potential ◽

Action Execution ◽

Additional Function ◽

Human Interface ◽

Hybrid Laminates ◽

Function Integration ◽

Materials Used

Achieving lightweight construction through only material substitution does not realize the full potential of producing a lightweight material, hence, it is no longer sufficient. Weight-saving goals are best achieved through additional function integration. In order to implement this premise for mass production, a manufacturing process for joining and forming hybrid laminates using a new tool concept is presented. All materials used are widely producible and processable. The manufactured cover of an automotive center console serves to demonstrate a human interface device with impact detection and action execution. This is only possible through a machine learning system, which is implemented on a small—and thus space- and energy-saving—embedded system. The measurement results confirm the objective and show that localization was sufficiently accurate.

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Durability of Titanium/Graphite Hybrid Laminates

Proceedings of the Eighth Japan-U.S. Conference on Composite Materials ◽

10.1201/9780367812720-32 ◽

2019 ◽

pp. 313-322

Author(s):

D. A. Burianek ◽

S. M. Spearing

Keyword(s):

Hybrid Laminates

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