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

Figure 8

Optical micrographs of wear scar diameter: (a) pure neem oil, (b) 0.25% GNPs-NO, (c) 0.50% GNPs-NO, (d) 0.75% GNPs-NO, and (e) 1.0% GNPs-NO.

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(b)

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