Investigation of the effect of different nano fluids on machinability in milling of Inconel 718 superalloy using minimum quantity of lubrication method (MQL)

Superalloys are materials that can meet the different needs demanded in the production of today's high-tech products. Nickel-based Inconel family of superalloys, which is widely used, stands out with its high tensile strength, creep resistance and corrosion resistance properties at high temperatures. In spite of the advantages given by the alloying elements in its structure, the negative contributions to its machinability are tried to be balanced by the researchers. For this reason, the effort to improve machinability by trying various methods in production processes has been the focus of the studies. Among these methods, the minimum amount of lubrication method is an important method that balances the response to the need for cooling with sensitivity to environmental protection and human health. The nanofluids created by adding nanoparticles to the cooling fluid used here offer remarkable contributions that can change the course of the event. Various nanofluids are tested in different manufacturing methods and their effects on the process are measured. Although the studies here are diverse and numerous, there are quite a few variations that have not yet been explored. Within the scope of this research, nanofluids that have not been studied before were tested with a minimum quantity of lubrication method in surface milling, where nanofluids have been studied very limitedly. These are designated as zinc oxide (ZnO), magnesium oxide (MgO) and molybdenum disulfide (MoS2). Three different nano fluids and additionally 4 different fluids with base fluid, 4 different cutting speeds, 4 different feed rates and 4 different depths of cut were tested for comparison. In order to measure the effects of cutting parameters, surface roughness measurements were taken from 3 different points on the surface at the end of each cut. Cutting forces were measured with a dynamometer connected to the bench, transferred to the computer and processed in the computer programme. The results were analysed by different methods. After each operation, the tool tip was removed and the amount of wear was examined under a microscope and the measurements were taken and recorded on the computer. As a result of the experiments, it was observed that nano fluids improved cutting parameters at varying rates. While nano fluids were effective on cutting force and surface roughness in the 3rd degree, they contributed the best effect on tool life. The lowest cutting force value was measured in the experiment with 35 m/min feed rate and 0.10 mm depth. The lowest roughness value among the nano fluids was observed in the experiment with 1% MoS2 nano fluid.