Graphene and carbon nanotube (GNT)-reinforced alumina nanocomposites

Toughening mechanisms and mechanical properties of graphene nanosheet-reinforced alumina

“…In case of Al 2 O 3 based composites, moderately higher fracture toughness values, by 27, 28, 33 and 53%, were reported for composites containing 0.3 [15] and 0.8 vol.% graphene [24] and 0.22 [25] and 2.0 wt.% graphene [26]. A recent approach involving use of both graphene and carbon nanotubes was employed by Yazdani et al to produce high performance Al 2 O 3 nanocomposites using hot pressing technique with reported increase in the fracture toughness and flexural strength values by 63 and a 15% [27]. One of the potential drawbacks associated with conventional pressureless sintering and hot-pressing (HP) techniques for ceramic composite fabrication are chemical/thermal deterioration of the graphene crystalline quality and grain growth of the matrix materials due to prolonged heating cycle [16,27].…”

“…A recent approach involving use of both graphene and carbon nanotubes was employed by Yazdani et al to produce high performance Al 2 O 3 nanocomposites using hot pressing technique with reported increase in the fracture toughness and flexural strength values by 63 and a 15% [27]. One of the potential drawbacks associated with conventional pressureless sintering and hot-pressing (HP) techniques for ceramic composite fabrication are chemical/thermal deterioration of the graphene crystalline quality and grain growth of the matrix materials due to prolonged heating cycle [16,27]. To eliminate these issues, novel sintering techniques involving relatively lower sintering temperatures and/or reduced dwell times at elevated temperatures, have been explored [28], rapid spark-plasma sintering (SPS) process one of them for fabrication of Al 2 O 3 /graphene nanocomposite [22][23][24][25][26].…”

Polymeric nanobiocomposites for biomedical applications

“…Similarly, PE and PLA have proven track records to be excellent candidates for bone tissue engineering due to their biocompatibility and non-toxicity, since they do not show much of an inflammatory response upon insertion into the body. 155,159,161 Some of the most accomplished fillers are silver, 162,163 carbon nanotube, 164 titanium dioxide, 95,165 silicon dioxide, 96,166 graphene dioxide, 158,167 and hydroxyapatite whiskers 128,168 and so forth These fillers can be successfully applied in dental and orthopedic application, since they can be easily incorporated into polymeric matrix by using methods, such as on-site precipitation, standard calandering technique or merely coating the nanofillers on to polymeric matrix. Among these fillers, carbon nanotubes have extensively been used for dental and orthopedic application owing to their superior ability to enhance mechanical properties, such as elastic modulus, young modulus, tensile strength upon addition of only minimal amount as less as 0.1% to the composites.…”

Mechanical and thermal properties of tungsten carbide – graphite nanoparticles nanocomposites

“…Anisotropy of properties usually occurs in hot-pressed materials when specifi c, directional orientation of graphene layers in composite microstructure is observed. Another effect in graphene composites is the improvement of the mechanical properties by bridging cracks through the layers of graphene by mechanism analogous to that in fi brous composites [10][11][12][13][14][15][16][17][18][19] . What is more, improvement of the tribological properties in composites containing platelet graphene is observed 19, 20 .…”