scholarly journals Improving the fracture toughness and the strength of epoxy using nanomaterials – a review of the current status

Nanoscale ◽  
2015 ◽  
Vol 7 (23) ◽  
pp. 10294-10329 ◽  
Author(s):  
N. Domun ◽  
H. Hadavinia ◽  
T. Zhang ◽  
T. Sainsbury ◽  
G. H. Liaghat ◽  
...  

The mechanical properties of epoxy reinforced by carbon nanotubes, graphene, nanosilica and nanoclays are reviewed and the effects of nanoparticles loading on enhancing the toughness, stiffness and strength are summarised.

2021 ◽  
Author(s):  
Radhika Wazalwar ◽  
Megha Sahu ◽  
Ashok M. Raichur

Epoxy composites find application in the aerospace industry. Although epoxy is a high-performance polymer, its fracture toughness is compromised due to its highly cross-linked nature. Nanomaterials such as carbon nanotubes...


Molecules ◽  
2021 ◽  
Vol 26 (15) ◽  
pp. 4423
Author(s):  
Marco A. Castro-Rojas ◽  
Yadira I. Vega-Cantu ◽  
Geoffrey A. Cordell ◽  
Aida Rodriguez-Garcia

Glass ionomer cements and resin-based composites are promising materials in restorative dentistry. However, their limited mechanical properties and the risk of bulk/marginal fracture compromise their lifespan. Intensive research has been conducted to understand and develop new materials that can mimic the functional behavior of the oral cavity. Nanotechnological approaches have emerged to treat oral infections and become a part of scaffolds for tissue regeneration. Carbon nanotubes are promising materials to create multifunctional platforms for dental applications. This review provides a comprehensive survey of and information on the status of this state-of-the-art technology and describes the development of glass ionomers reinforced with carbon nanotubes possessing improved mechanical properties. The applications of carbon nanotubes in drug delivery and tissue engineering for healing infections and lesions of the oral cavity are also described. The review concludes with a summary of the current status and presents a vision of future applications of carbon nanotubes in the practice of dentistry.


2013 ◽  
Vol 761 ◽  
pp. 83-86
Author(s):  
Hideaki Sano ◽  
Junichi Morisaki ◽  
Guo Bin Zheng ◽  
Yasuo Uchiyama

Effects of carbon nanotubes (CNT) addition on mechanical properties, electric conductivity and oxidation resistance of CNT/Al2O3-TiC composite were investigated. It was found that flexural strength, Young’s modulus and fracture toughness of the composites were improved by addition of more than 2 vol%-CNT. In the composites with more than 3 vol%-CNT, the oxidation resistance of the composite was degraded. In comparison with Al2O3-26vol%TiC sample as TiC particle-percolated sample, the Al2O3-12vol%TiC-3vol%CNT sample, which is not TiC particle-percolated sample, shows almost the same mechanical properties and electric conductivity, and also shows thinner oxidized region after oxidation at 1200°C due to less TiC in the composite.


2017 ◽  
Vol 2017 ◽  
pp. 1-9 ◽  
Author(s):  
Carlos Medina ◽  
Eduardo Fernandez ◽  
Alexis Salas ◽  
Fernando Naya ◽  
Jon Molina-Aldereguía ◽  
...  

The mechanical properties of the matrix and the fiber/matrix interface have a relevant influence over the mechanical properties of a composite. In this work, a glass fiber-reinforced composite is manufactured using a carbon nanotubes (CNTs) doped epoxy matrix. The influence of the CNTs on the material mechanical behavior is evaluated on the resin, on the fiber/matrix interface, and on the composite. On resin, the incorporation of CNTs increased the hardness by 6% and decreased the fracture toughness by 17%. On the fiber/matrix interface, the interfacial shear strength (IFSS) increased by 22% for the nanoengineered composite (nFRC). The influence of the CNTs on the composite behavior was evaluated by through-thickness compression, short beam flexural, and intraply fracture tests. The compressive strength increased by 6% for the nFRC, attributed to the rise of the matrix hardness and the fiber/matrix IFSS. In contrast, the interlaminar shear strength (ILSS) obtained from the short beam tests was reduced by 8% for the nFRC; this is attributed to the detriment of the matrix fracture toughness. The intraply fracture test showed no significant influence of the CNTs on the fracture energy; however, the failure mode changed from brittle to ductile in the presence of the CNTs.


2009 ◽  
Vol 66 ◽  
pp. 288-291
Author(s):  
Li Wei Huang ◽  
Zheng Yi Fu ◽  
Jin Yong Zhang ◽  
Wei Min Wang ◽  
Hao Wang ◽  
...  

Carbon nanotubes reinforced alumina was fabricated by spark plasma sintering method. When adding 0.2wt% nanotubes, the fracture toughness of the composites prepared increases 19% compared with the pure alumina ceramics. The effect of sintering schedule on microstructure and mechanical properties is investigated systematically. Microstructure studies reveal that at high sintering temperature, the nanotubes tend to gather in the gaps surrounded by three or more grains in a flocculent state, which leads to poor mechanical properties. Raman spectrum indicates that long sintering duration may cause serious nanotubes destruction and lower the mechanical properties.


2012 ◽  
Vol 32 (4-5) ◽  
pp. 311-317
Author(s):  
Abdolhossein Fereidoon ◽  
Lia Mottahedin ◽  
Sara Tahan Latibari

Abstract The effects of single-walled carbon nanotubes (SWCNTs) on the mechanical properties of nanocomposites with epoxy matrix were studied, with the emphasis on fracture toughness under tensile loading conditions. It has been demonstrated that adding CNTs into polymer-based materials can improve the mechanical properties of this material. CNTs possess a certain potential to improve the fracture toughness of epoxy systems due to their mechanical properties and increase the fracture toughness of nanocomposites. Since the fracture toughness parameters were best manifested in the scaling properties and were the main parameters, the angles of different cracks have been simulated in a 3D finite element framework and the effects of different angles of crack, on the fracture toughness of polymers, have been modeled and investigated. The simulations are run for different bias angles. The influence of angle, the crack lengths and the variations of different lengths of nanocomposite in different volume fractions (vol%) are investigated. That is to say, at first, nanocomposites had a significantly higher fracture toughness compared to the pure epoxy. We found that nanocomposites, in the presence of SWCNTs, had a greater effect on fracture toughness of nanocomposites in a greater volume of fractions. Also, the nanocomposites exhibited a significant increase in fracture toughness, with zero angle of crack compared with greater angles. In addition, it is found that at a constant volume fracture, fracture toughness, increases by increasing crack lengths.


2019 ◽  
Vol 54 (17) ◽  
pp. 2353-2363
Author(s):  
SH Mussavi Rizi ◽  
M Ghatee

This paper reports the effects of adding carbon nanotubes on the mechanical properties of zirconia-toughened alumina thick films prepared by tape casting. Polyvinylpyrrolidone, polyvinyl alcohol, and glycerin were used as dispersant, binder, and plasticizer, respectively. The microstructure and phase content of the samples were studied using scanning electron microscopy and X-ray diffraction methods, respectively. Mechanical properties of thick composite films were investigated by microhardness and nanoindentation methods. It was determined that polyvinylpyrrolidone can be used as a dispersant for carbon nanotube, alumina, and zirconia particles; tape casting can produce thick films with homogeneous phase distribution, and that adding up to 0.01 wt.% carbon nanotube enhanced the zirconia-toughened alumina hardness by more than 30%, and fracture toughness about 40%. Increasing carbon nanotube content over 0.01 wt.% up to 0.1 wt.% increases microhardness and nanohardness but does not affect fracture toughness significantly.


2013 ◽  
Vol 423-426 ◽  
pp. 38-42
Author(s):  
Ai Min Li ◽  
Kang Ning Sun ◽  
Run Hua Fan

Carbon nanotubes/zirconia/hydroxyapatite biocomposites was prepared by hot-pressing sintering under Ar atmosphere. The influence of sintering temperature on the mechanical properties and microstructure of carbon nanotube/zirconia/hydroxyapatite biocomposites was studied. We tested the bending strength and fracture toughness by universal electronic materials testing machine. The component of the composites was tested by XRD. The fracture surface of the composites was observed by SEM. The results indicate that the bending strength and fracture toughness of the composites is lower when the sintering temperature is lower than 1200°C. The difference of bending strength and fracture toughness at 1200°C and 1300°C is little. The number of them has risen markedly than the low temperature which reached to189.2MPa and 1.8MPa·m-1/2 respectively. The composition of the composites is mainly of hydroxyapatite, zirconia, carbon nanotubes, and a small amount of calcium phosphate, which indicated that part of the hydroxyapatite has decomposed. SEM photographs show that the fracture surface of the composites sintered at 1200 °C and 1300 °C is ductile fracture status and has bigger density.


This study aims to develop and determine mechanical properties chopped basalt fibre reinforced composites (CBFRP) modified with multiwall carbon nanotubes (CNT). Chopped basalt composite modified with CNT was fabricated using a combination of mechanical stirring and hand layup process. Three different weight percentages of CNT i.e. 0.5, 1, 1.5wt. % were filled into epoxy resin before mixing with chopped basalt fiber. The mechanical performance namely tensile properties and fracture toughness behaviour of the fabricated chopped basalt composites was assessed using Universal Testing Machine in accordance to ASTM standard D368 and D695, respectively. The results showed that the incorporation of CNT enhanced tensile and fracture toughness properties of the CBFRP composites. However, a higher amount of CNT (1.5wt%) incorporated into the CBFRP caused reduction in tensile strength, tensile modulus and Gic by 4.40%, 2.46% and 30.36 %, respectively, as compared to those of 1.0CNT-CBFRP


Cerâmica ◽  
2018 ◽  
Vol 64 (372) ◽  
pp. 608-615 ◽  
Author(s):  
C. A. de O. Couto ◽  
S. Ribeiro ◽  
F. R. Passador

Abstract Toughened and hardened alumina/carbon nanotubes and zirconia-toughened alumina (ZTA)/carbon nanotubes nanocomposites were developed by conventional ceramics route using pressureless sintering for the ballistic application. The multiwall carbon nanotubes (CNT) were functionalized with nitric acid oxidation reaction. Moreover, the surfactants sodium dodecyl sulphate and gum arabic were used to promote a homogeneous distribution of CNT in the ceramic matrix. Ceramic powders were prepared with pure alumina, alumina with the addition of 20 wt% of tetragonal zirconia/yttria, alumina/CNT and ZTA/CNT with the addition of 0.1 and 0.5 wt% of CNT. The morphology of nanocomposites was characterized by SEM-FEG. The mechanical properties of sintered samples were evaluated by flexural bending, Vickers microhardness and fracture toughness by SEVNB method. The addition of CNT in the ceramic and composite caused a general increase in densification, hardness, flexural strength and fracture toughness. ZTA composite with the addition of 0.1 wt% of CNT yielded the best results.


Sign in / Sign up

Export Citation Format

Share Document