Effects of hybrid nanofluids on machining performance in MQL-milling of Inconel X-750 superalloy

Abstract

Friction and high temperatures greatly affect machining efficiency when machining superalloy materials. Nanoparticles with high thermal conductivity and lubricity are preferred for increase lubricant performance. Nanofluids prepared with nanoparticles not only reduce environmental concerns but also positively affect the machining efficiency in the sustainable manufacturing process. However, some nanoparticles added in mono form stand out with their thermal conductivity and some nanoparticles with their lubricating performance. For this reason, the lubrication performance of hybrid nanofluids prepared with nanoparticles with different superior properties is a matter of interest. In this study, the machining performance of Inconel X-750 superalloy was investigated by using hexagonal boron nitride (hBN), graphite (Grpt), and MoS2 nanoparticles with different shapes and properties. For this purpose, the milling experiments were performed under three different hybrid nanofluid (hBN/Grpt, hBN/MoS2, and Grpt/MoS2) conditions, at three different cutting speeds (30, 45, and 60 m/min), and three different feed rates (0.05, 0.10, and 0.15 mm/rev). Cutting force, cutting temperature, surface roughness/topography, tool wear, and tool life were selected as machining performance criteria. According to the results obtained from the experiments, it was understood that the hBN/Grpt hybrid nanofluid outperformed hBN/MoS2 and Grpt/MoS2 conditions in all performance criteria. hBN/Grpt hybrid nanofluid achieved 36.17% and 6.08% improvement in tool life compared to Grpt/MoS2 and hBN/MoS2 nanofluids, respectively.