Carbon nano dots mixed rice bran oil as a cutting fluid for enhanced lubrication/cooling in milling of additively manufactured 316 stainless steel

Abstract

Nanofluids, which have improved thermal conductivity compared to regular lubricants, can assist in the dissipation of heat while cutting materials. A colloidal suspension can be formed by dispersing nanoparticles within a base fluid. Their high thermal conductivity and viscosity make them a promising heat transfer fluid option; by using nano-additives, their cooling and lubricating capabilities may be further improved. Recently, carbon nanodots have grabbed the attention due to their many desirable characteristics, including their high solubility, chemical inertness, and low toxicity. Therefore, in this perspective, the thermophysical properties of rice bran oil enriched with carbon nanodots and their considerable impact on the machinability of 316 stainless steel produced additively has been examined. The different wt.% (0–1.25) of carbon nanodots are dispersed in rice bran oil to test the wettability, thermal conductivity, and dynamic viscosity. After that, milling tests are conducted under dry, flood, minimum quantity lubrication, and nano-minimum quantity lubrication conditions. The findings admit that the inclusion of nanoparticles in rice bran oil at 1 wt.% results in lower contact angle, higher thermal conductivity, and higher viscosity. In addition, the employment of nanoparticles in minimum quantity lubrication reduced the roughness by 60–63 %, 40–43 %, and 22–25 % in relation to dry, flood, and MQL conditions, respectively. The reduction in roughness has a direct influence on tool wear.