Mitigation of chemical wear by graphene platelets during diamond cutting of steel

Abstract

The diamond cutting of transition metal alloys, particularly steel, is severely hindered by accelerated chemical wear of the tool. Recent experimental findings show that the presence of graphene platelets mitigates this problem. However, the specific mechanisms responsible for this wear mitigation are currently unknown. In this paper, molecular dynamics techniques are successfully used to identify these diamond tool wear mitigation mechanisms. A modified embedded atom method force field is first evaluated for its ability to accurately simulate the catalyzed graphitization of diamond in the presence of steel. This force field is then used to simulate nanometric diamond cutting of steel in the presence of a 1 or 3 layered graphene platelet. Coordination analysis of these simulations shows that the presence of the graphene platelet results in 34%-96% reduction in tool wear, when compared to the graphene-free cutting condition. This is attributed to the graphene platelet serving as a physical barrier protecting the tool cutting edge, and also as a sacrificial source for carbon transfer into the workpiece. Other mechanisms, such as platelet cleaving and interlayer sliding, are also observed. The reduction in tool wear reported by the simulations is comparable to the trends observed in prior experiments.

Mixed sp2–sp3 Nanocarbon Materials: A Status Quo Review

“…The strengthening mechanism in the GN/PDC composite is due to the well-known lubrication effect of the GN/diamond interface. In this vein, GN pallets are very efficient in suppressing the chemical wear of the tool in diamond cutting [158]. The GO helps improve the wear resistance of the epoxy resin-bonded diamond abrasive tools [159].…”

Graphene – Diamond Nanomaterials: A Status Quo Review

“…The strengthening mechanism of PDC-G mainly occurred as a result of the lubricating effect of graphene between diamond particles. Graphene pallets are very efficient in suppressing the chemical wear of the tool in diamond cutting [138].…”

Covalently Bonded Heterostructures with Mixed-Dimensional Carbons for Suppressing Mechanochemical Wear of Diamond under Heavy Loads

“…16−18 For example, when graphene was used as a nanoadditive (weight loading of 0.2%) in cutting fluids to cut steel with diamond tools, it could reduce the wear of diamond tools by 32%. 17 Compared with other twodimensional lubricating materials, graphene as a nanoadditive of cutting fluid had the best effect of suppressing diamond mechanochemical wear, and the wear rate of diamond tools was reduced by up to 60%, followed by hexagonal boron nitride, tungsten disulfide, and molybdenum disulfide, with wear reduction rates of 52, 45, and 38%, respectively. 18 However, the effectiveness of graphene as a nanoadditive is limited by its difficulty in fully entering the actual friction interface, which weakens its suppression ability.…”

“…Graphene, a two-dimensional lubricating material with an atomic thickness, was discovered at the beginning of this century and has exceptional properties, including extremely high strength and good chemical stability . Using graphene to suppress the mechanochemical wear of diamond surfaces could become a more practical, economical, and attractive approach since it does not affect the use of existing equipment and processing accuracy. − For example, when graphene was used as a nanoadditive (weight loading of 0.2%) in cutting fluids to cut steel with diamond tools, it could reduce the wear of diamond tools by 32% . Compared with other two-dimensional lubricating materials, graphene as a nanoadditive of cutting fluid had the best effect of suppressing diamond mechanochemical wear, and the wear rate of diamond tools was reduced by up to 60%, followed by hexagonal boron nitride, tungsten disulfide, and molybdenum disulfide, with wear reduction rates of 52, 45, and 38%, respectively .…”