Tribological Behaviour of Neem Oil with and without Graphene Nanoplatelets Using Four-Ball Tester

Figure 13

Optical micrographs showing wedge cutting edge and pit formation: (a) wedge cutting edge in NO, (b) Pit in Pure NO, (c) 0.25% GNPs-NO, and (d) 0.5% GNPs-NO.

(a)

(b)

(c)

(d)