Investigations on the impact behaviour of fibre-reinforced composites: effect of impact energy and impactor shape

With the exceptional mechanical properties, carbon nanotubes (CNTs) are considered to be attractive candidate reinforcements for composite materials and to have potential applications in improving the energy absorption capability of matrix material. However, it is still difficult to reveal the micro-mechanisms of the impact energy absorption of CNT-reinforced composites by experiments, hence, the numerical investigation is helpful. In this paper, a unit cell of single-walled CNTs (SWCNTs) embedded in metal matrix is modeled by nano-scale finite element method. Under impact loads, the failure modes of a single SWCNT and the SWCNT in matrix are predicted, respectively, and several possible energy absorption mechanisms are explained and compared. The investigation shows that, the metal matrix restraints the radial expansion of the SWCNT and therefore improves its crush buckling resistance, and makes it absorb more energy before collapse. The specific energy absorption of SWCNTs-reinforce composites increases with the increasing volume fraction of SWCNTs in both matrixes, and ascends more quickly in magnesium alloy than in aluminum alloy matrix.

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An Experimental and Numerical Study on the Impact Energy Absorption Characteristics of the Multiaxial Warp Knitted (MWK) Reinforced Composites

Journal of Composite Materials ◽

10.1177/0021998305047099 ◽

2005 ◽

Vol 39 (6) ◽

pp. 525-542 ◽

Cited By ~ 18

Author(s):

Zhou Rongxing ◽

Hu Hong ◽

Chen Nanliang ◽

Feng Xunwei

Keyword(s):

Energy Absorption ◽

Impact Energy ◽

Numerical Study ◽

Reinforced Composites ◽

The Impact ◽

Absorption Characteristics

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Charpy test investigation of the influence of fabric weave and fibre nature on impact properties of PEEK-reinforced composites

Journal of Thermoplastic Composite Materials ◽

10.1177/0892705718778744 ◽

2018 ◽

Vol 32 (6) ◽

pp. 729-745 ◽

Cited By ~ 3

Author(s):

Olivier De Almeida ◽

Jean-François Ferrero ◽

Laurent Escalé ◽

Gérard Bernhart

Keyword(s):

Energy Absorption ◽

Failure Modes ◽

Charpy Impact ◽

High Strength ◽

Charpy Impact Test ◽

Reinforced Composites ◽

Charpy Test ◽

Impact Behaviour ◽

Weave Pattern ◽

The Impact

The aim of the work is to use Charpy impact test for quick evaluations of different Polyether-ether-ketone (PEEK)-reinforced composites to be used for impact protection. In the first part, the influence of weave pattern was first analysed by comparing the impact behaviour of three PEEK composites reinforced with plies of unidirectional (UD) tapes, 5H satin fabrics and 2 × 2 twill fabrics made of high-strength carbon fibres. In the second part, the influence of fibre nature was investigated for the same weave pattern. The impact behaviour of five 2 × 2 twill fabrics made from inorganic fibre (carbon, glass and basalt) and organic fibre (aramid and poly(p-phenylene-2,6-benzobisoxazole) (PBO)) has been compared. Two main types of failure modes were identified: a brittle behaviour mode with high failure strength and a highly deformable behaviour mode in which energy absorption is more important. The balance between brittle behaviour and highly deformable behaviour results from competition between the yarn crimp, weave pattern and fibre properties of the composite. Slight yarn crimp and small ply thickness increase the stiffness of the composite and induce brittle behaviour characterized by fibre failure in tension and a steep peak on the loading curves. This behaviour is observed in UD and 5H satin carbon-reinforced composites or 2 × 2 twill glass and basalt fabric-reinforced composites. In contrast, aramid and PBO 2 × 2 twill fabric composites exhibit high shear strength. The highly deformable behaviour of the specimens during the Charpy impact led, in the case of organic fibres, to a non-breakage of the fibres and consequently to a high level of energy absorption. This behaviour is necessarily interesting in armour applications.

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The Impact Toughness and Hardness of Treated and Untreated Sisal Fibre-Epoxy Resin Composites

Advances in Materials Science and Engineering ◽

10.1155/2018/8234106 ◽

2018 ◽

Vol 2018 ◽

pp. 1-10 ◽

Cited By ~ 4

Author(s):

Wilson Webo ◽

Leonard Masu ◽

Maina Maringa

Keyword(s):

Impact Toughness ◽

Epoxy Resin ◽

Chemical Treatment ◽

Alkali Treatment ◽

Reinforced Composites ◽

Mechanical Interlocking ◽

Sisal Fibre ◽

Treatment Processes ◽

The Impact ◽

Fibre Reinforced Composites

The effect of the combined chemical treatment of sisal fibres through the subsequent processes of mercerisation (alkali treatment), then silane treatment and eventually acid hydrolysis, on sisal fibre was investigated. The effect of the treated fibres on the impact toughness and hardness of their composites with epoxy resin was also studied. Scanning electron microscopy of the surfaces of the treated and untreated fibres showed that the chemical treatment processes enhanced the removal of surface impurities and therefore increased the roughness of the surfaces of the fibres. This avails an increased surface area for interlocking with matrix and is, therefore, expected to enhance adhesion of the two. The treated fibre reinforced composites were observed to have higher values of impact toughness and hardness than the untreated fibre reinforced composites. These higher values were attributed to better interfacial bonding due to better mechanical interlocking between the treated fibres and epoxy resin arising from the increased roughness of the treated fibres.

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Variation in Heat Deflection Behaviour of Alkali Treated and Untreated Hybrid Fibre Reinforced Composites

International Journal of Engineering and Advanced Technology - Regular Issue ◽

10.35940/ijeat.f1277.0886s219 ◽

2019 ◽

Vol 8 (6S2) ◽

pp. 765-767

Keyword(s):

Glass Fiber ◽

Flax Fiber ◽

Reinforced Composites ◽

Hybrid Fibre ◽

The Impact ◽

Normal Fiber ◽

Fibre Reinforced Composites ◽

Basic Treatment ◽

Glass Mixture

Regular Fiber fortified composites discovers place in numerous applications as they have the benefits of being light, solid, modest and progressively ecological well disposed. This investigation planned to decide the impact of antacid treatment on normal fiber and its effect on the warmth diversion conduct of the regular and glass fiber fortified cross breed composites ,in this work two kind of half and half composite are made with glass, sisal and flax fiber ,the crossover strengthened composite covers were manufactured by hand lay-up technique. Examples are cut from the manufactured cover and their warmth diversion conduct was tried by ASTM D648 benchmarks. From the outcome it is comprehended that the basic treatment has improved the warmth avoidance withstanding limit of flax/glass half and half composite and don't have much impact on sisal/glass mixture composite.

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