The density effect of van der Waals forces on the elastic modules in graphite layers

Dense graphene nanoplatelet/yttria tetragonal zirconia composites: Processing, hardness and electrical conductivity

“…6). This can be due to the intrinsic properties of the GNPs, such as the increased bending rigidity in the principal (in-plane) direction [15], although the extremely high Young's modulus reported for monolayer graphene decreases with the increasing number of layers [48]. Our results are also in agreement with authors [49] who have reported that the indentation load required to achieve a certain displacement is much higher when the indentation occurs on the orthogonal surface of an SPSed multilayered graphene surface than when it occurs on the top surfaces.…”

Elastic properties of silicon nitride ceramics reinforced with graphene nanofillers

“…These E data are rather low if we consider the in-plane elastic modulus (0.6-1 TPa) reported for either graphite or graphene [13,21,22]; and although numerical modeling indicates a decrease of E with the number of graphene layers, values always remain above 0.9 TPa [23,24].…”

In situ indentation behavior of bulk multi-layer graphene flakes with respect to orientation

“…Golkarian et al [10] reported on the effect of the van der Waals forces when increasing the number of layers in graphite flakes and found by theoretical modeling that the Young's modulus decreased about 13% with increasing the number of layers fourfold. Nanoindentation, previously performed on fully dense samples of MLG consolidated by spark plasma sintering (SPS), showed a correlation of mechanical properties as a function of loading direction [11].…”