Improvement in Mechanical Properties of Continuous Carbon Fiber Reinforced Thermoplastic Composites by Ozone Oxidation Treatment

The main objective of this study was to investigate contribution of the non-functionalized multi-walled carbon nanotubes on the vibration damping behavior of first neat epoxy resin and then unidirectional and bidirectional continuous carbon fiber reinforced epoxy matrix composites. Epoxy/carbon nanotubes nanocomposites were produced by ultrasonic solution mixing method, while the continuous carbon fiber reinforced composite laminates were obtained via resin-infusion technique. Vibration analysis data of the specimens were evaluated by half-power bandwidth method; and the mechanical properties of the specimens were determined with three-point bending flexural tests, including morphological analyses under scanning electron microscopy. It was generally concluded that when even only 0.1 wt% carbon nanotubes were incorporated into neat epoxy resin, they have contributed not only to the mechanical properties (flexural strength and modulus), but also to the vibration behavior (damping ratio) of the epoxy. When 0.1 or 0.5 wt% carbon nanotubes were incorporated into continuous carbon fiber reinforced epoxy matrix composites, although they have no additional contribution to the mechanical properties, their contribution in terms of damping ratio of the composites were significant.

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Postprocessing method-induced mechanical properties of carbon fiber-reinforced thermoplastic composites

Journal of Thermoplastic Composite Materials ◽

10.1177/0892705720945376 ◽

2020 ◽

pp. 089270572094537

Author(s):

Van-Tho Hoang ◽

Bo-Seong Kwon ◽

Jung-Won Sung ◽

Hyeon-Seok Choe ◽

Se-Woon Oh ◽

...

Keyword(s):

Mechanical Properties ◽

Carbon Fiber ◽

Processing Parameters ◽

Thermoplastic Composites ◽

Void Content ◽

Fiber Reinforced ◽

Crystallinity Degree ◽

Automated Fiber Placement ◽

Carbon Fiber Reinforced

Promising carbon fiber-reinforced thermoplastic (CF/polyetherketoneketone (PEKK)) composites were fabricated by the state-of-the-art technology known as “Automated Fiber Placement.” The mechanical properties of CF/PEKK were evaluated for four different postprocessing methods: in situ consolidation, annealing, vacuum bag only (VBO), and hot press (HP). The evaluation was performed by narrowing down the relevant processing parameters (temperature and layup speed). Furthermore, the void content and crystallinity of CF/PEKK were measured to determine the effect of these postprocessing processes. The HP process resulted in the best quality with the highest interlaminar shear strength, highest crystallinity degree, and lowest void content. The second most effective method was VBO, and annealing also realized an improvement compared with in situ consolidation. The correlation between the postprocessing method and the void content and crystallinity degree was also discussed.

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Experimental Investigation on the Dynamic Properties and Failure Mode of Carbon Fiber Reinforced Thermoplastic Composites

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.697.102 ◽

2014 ◽

Vol 697 ◽

pp. 102-108

Author(s):

Jian Hua Ning

Keyword(s):

Mechanical Properties ◽

Carbon Fiber ◽

Strain Rate ◽

Failure Modes ◽

Thermoplastic Composites ◽

Elastic Model ◽

Strength Increase ◽

Fiber Reinforced ◽

Carbon Fiber Reinforced ◽

Constitute Model

Owing to the excellent mechanical properties and formability of carbon fiber reinforced thermoplastic composites, this composite has been applied in car industry. The static and dynamic mechanical properties of the composites are investigated under strain-rate from 0.001/s to 50/s. The experimental results show that the elastic model and tensile strength increase with the increase of strain rate, and show that the composite has remarkable rate-hardening effect. A constitute model that including rate-dependent effect is applied to present the strain-stress curve of the composite. The constitute model provides accurate constitute function for finite element analysis of the composite.. The microstructure of the composite is also investigated with scanning electric microscope, and the failure modes are discussed. The investigation provides the basis for engineering application of the composite.

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