Brittle and ductile removal modes observed during diamond turning of carbon nanotube composites

Abstract

International audienceUltraprecision diamond turning was used to evaluate the surface integrity of a carbon nanotube (CNT) composite as a function of the cutting conditions and the percentage of CNT in the epoxy matrix. The effects of cutting conditions on the chip morphology and surface roughness were analysed. The results showed that an increase in the percentage of CNT may influence the mechanism of material removal and consequently improve the quality of the machined surface. When smaller quantities of CNT (0.02 and 0.07 wt %) are present in the matrix, microcracks form within the cutting grooves (perpendicular to the cutting direction). This indicates that the amount of CNT on the epoxy matrix may have a direct influence on the mechanical properties of these materials. Chips removed from the CNT composite samples were analysed by scanning electron microscopy in order to correlate the material removal mechanism and the surface generation process. The area average surface roughness Sa was influenced by the material removal mechanism (Sa ranging from 0.28 to 1.1 μm)

Experimental Investigation of the Machinability of Epoxy Reinforced With Graphene Platelets

“…So the preferred cutting speed that achieves a low surface roughness value appears to be the lowest cutting speed of 7 m/min. This is consistent with the findings for machining brittle materials [28].…”

Experimental Investigation on Micro Milling of Polyester/Halloysite Nano-Clay Nanocomposites

“…This is due to the limited effect of halloysite nano clay on improving fracture toughness [43]. If the nanoparticle can significantly improve the fracture toughness [43,45], the surface roughness of polymer composites will first decrease and then increase as the value of FPT increase. The increase of fracture toughness is too small to cause a change in the facture mode [43].…”