Properties of 3Y-TZP zirconia ceramics with graphene addition obtained by spark plasma sintering

Flexure Strength and Fracture Propagation in Zirconia Ceramic Composites with Exfoliated Graphene Nanoplatelets

“…The composite powders with 1 vol.% e-GNP exhibited the highest ID/IG ratio, which may indicate that ball milling is more effective in lateral size reduction of the GNP with a higher ceramic/GBN ratio. Milling of compositions with higher GNP content was less aggressive since the GNPs possess a lubricating effect [7,9]. All the spectra present characteristic D and G peaks centered at~1350 and~1580 cm −1 , respectively, as well as the splitting of 2D Raman-active bands centered at~2700 cm −1 .…”

“…Fracture toughness enhancements up to 61% were reported for very low additions (0.01 wt.%) of few layered graphene [20] while more modest enhancements were reported for 4.1 vol.% reduced graphene oxide (rGO) addition [12] and 1 wt.% graphene oxide (GO) [21]. Recently, Obradovic and Kern [9] found only a slight increase (~2%) in fracture toughness in 3YTZP composites with 1-2 vol.% GNP content and a decrease for higher GNP contents, using indentation strength in bending (ISB). These authors compared DCM and ISB methods and concluded that DCM results fluctuated randomly; thus, this method is not reliable to test fracture toughness in 3YTZP-GNP composites.…”

“…The literature on mechanical properties of ceramic composites with GBN reports a decrease in hardness and Young's modulus with increasing GBN content [9][10][11][12][13][14][15], while the results on fracture toughness and flexural strength vary in a large range. Many authors estimated fracture toughness of ceramic GBN composites from direct crack measurement (DCM) after indentation tests (a quite simple and easy technique), but this method fails to provide reliable results with carbonaceous phases such as carbon nanotubes or graphite as fillers [16].…”

“…Li et al [22] found no increase in flexural strength in three-point bending with addition of 0.5 to 1.5 wt.% GNP, although fracture toughness increased by 10% in single edge v-notched beam (SEVNB) for 1 wt.% GNP. Obradovic and Kern [9] tested composites with 1-4 vol.% GNP in four-point bending and found an exponential decrease in flexural strength with GNP addition, which was attributed to porosity and structural defects introduced by the GNP.…”

Research on the interface properties and strengthening–toughening mechanism of nanocarbon-toughened ceramic matrix composites

“…have excellent thermal, electrical, and mechanical properties. Extensive research has shown that nanocarbon can enhance many properties of ceramics, for example, the mechanical, frictional [6][7][8][9], electrical [10][11][12][13], and thermal properties [14][15][16]. As a result, nanocarbon is regarded as an ideal reinforcing phase in ceramic matrix materials.…”