Application of a tailored eco-friendly nano fluid in pressurized internal-cooling grinding of Inconel 718

In the precision machining and ultra-precision machining of superalloy, grinding fluids are used for cooling and lubricating to improve machining quality and efficiency, nevertheless conventional grinding fluid is harmful to human health and is neither environmental nor economical. As a novel cooling and lubricating medium, nanofluid exhibits excellent cooling and lubrication properties. In this paper, a tailored eco-friendly Al2O3/soybean oil nanofluid is developed for pressurized internal-cooling grinding of Inconel 718, the thermo-physical and tribological properties of the tailored nanofluid are studied initially, furthermore soybean oil, Al2O3/soybean oil nanofluid and conventional grinding fluid are respectively used in pressurized internal-cooling grinding Inconel 718, finally the grinding temperature and surface integrity under three various grinding fluid conditions are compared and analyzed. It can be revealed that the Al2O3/soybean oil nanofluid could result in both a best surface integrity and a lowest grinding temperature relatively, the EDS analysis presumably demonstrates that the Al2O3 nanoparticles play the role of "bearing effect" and a certain "self-repairing effect", which improves the machined surface integrity significantly. In general, it indicates that the tailored grinding fluid is effective, non-toxic and economical, additionally the proposed grinding method also shows excellent potential to apply in the aviation manufacturing industry. (C) 2020 Elsevier Ltd. All rights reserved.