Tribological behavior of the boric acid and titanium dioxide based nanofluid in machining of EN24 steel

Abstract

Turning operation is a widely recognized metal removal process in the industry. If the machining were not run efficiently, it may affect the performance of the tool and the work piece by generating higher cutting forces and the temperature as in hard steel. To minimize these effects, lubrication has to be effective in reducing these forces and lowering the tool temperature. In the present study, machining experiments were conducted on EN24 steel with the application of nano sized boric acid (50 nm) as the solid lubricant that is mixed with titanium dioxide (100 µm) in SAE 40 oil. Turning tests are conducted using tungsten carbide tool inserts under dry, wet and MQL conditions to measure and compare the cutting forces, tool temperatures and roughness of the work piece. Results indicate that boric acid enables significant reduction in the cutting forces which in combination with the titanium dioxide helps to improve the heat dissipation; an advantage that makes such lubricants an effective cutting fluid. H3BO3 and TiO2 based nanofluid resulted in reducing the surface roughness of up to 2.7 µm that is a re-duction by ~15%.

A critical review of the effect of nano-lubricant on the performance of hydrodynamic journal bearing

“…Various rheological tests of nano-lubricants confirm that the nano-additives increase the viscosity of base lubricant [28][29][30][31][32][33], control the reduction of the viscosity with increasing temperature and enhances the thermal conductivity [29][30][31][32]34], which improves the static [13,14,35] and dynamic performance [20,36] of the bearing. The inclusion of nano-additives in lubricant significantly improves the tribological properties of the lubricant [37][38][39][40][41]. Tribological tests performed on pin-on- disk [40], four ball tribo-tester [42] reported reduced friction and wear [43][44][45][46][47][48][49][50][51][52] with the addition of nanoparticles in mineral oils due to a reduction in real area of contact of the mating parts [53].…”