Investigation of Machinability of Polymer/Nanoparticle Nanocomposites

Abstract

With the development of composite materials, the addition of small amounts of nanoparticles to the matrix material can significantly alter its. The change in properties allows a wider range of applications for nanocomposites, and research into the processing of materials is essential to ensure that future applications are carried out successfully. This study investigates how the size of nanoparticles affects the cutting properties of materials and to clearly and accurately determine the machining properties of polymer nanocomposites. Experimental and simulation methods are used to investigate the machinability of nanocomposites. Based on possible scenarios of future high-precision applications of polymer nanocomposites, experiments are conducted using micromilling machining, while the finite element (FE) method is used in simulations to replace the previously employed molecular dynamics (MD) method. The new method significantly reduces the simulation time from approximately ten days of computing on a desktop workstation to a few hours on a personal laptop. The effects of various types and weight fractions of graphene nanoplatelets (GNP), nano clay and carbon nanotube (CNT) nanoparticles on machining performance, including surface morphology, burr formation, cutting force and specific cutting energy, and tool wear, are studied. The size effect in micromachining is also considered. Different nanoparticles are found to have different effects on cutting performance, with graphene improving the accuracy of the cutting surface, CNT particles increasing the cutting force more significantly, and nano clay particles having little effect on the accuracy of the machined surface. The simulation study includes the realization of a constitutive model for the polymer in commercial software and the design of a finite element analysis cutting model for nanocomposite materials. Finally, the simulation and experimental results are compared and verified by investigating cutting force, tool-particle interaction, nanoparticle fracture behaviour, stress/strain distribution, chip formation process and surface. The validation of the model is carried out by studying chip morphology, cutting force, and surface morphology data obtained from machining experiments, and the simulation results are in good agreement with those of the experiments. It is concluded that GNP nanoparticles can be used for material machining accuracy and FE simulation methods can be used for polymer machining simulation processes in order to reduce the calculation time.