Enhancement of thermo-physical and lubricating properties of SiC nanolubricants for machining operation

摘要

Vegetable oils have been adjudged a suitable replacement for conventional cutting fluid in metal cutting process because of its biodegradability, less toxic, high lubricity and environmental friendly. However, efficient performance of vegetable oil has been limited when machining at higher cutting speed or elevated temperature as the cutting fluid evaporates when in contact with cutting tools already heated to high cutting temperature. Thus, nanoparticles are introduced into base lubricating oils to improve their thermal and lubricating properties. The present work is to investigate the thermal and lubricating properties of coconut oil-based Silicon Carbide (SiC) nanofluid at varying concentration of 0.35wt.%, 0.7wt.% and 1.05wt.%. Thermal conductivity and viscosity of the nanofluid was measured with the aid of KD2 Pro thermal analyser and LVDV-III Rheometer respectively while the four-ball wear and friction tester will be used to measure anti-wear property of the nanofluid. Thermal conductivity and viscosity of nanofluid improved with increase of nanoparticle concentration but decrease with increase of temperature. The highest ratio of enhancement of thermal conductivity of is 1.038 while increase of viscosity of nanofluid at temperatures of 30°C and 70°C are 1.277 and 1.397 respectively. The nanofluid was deficient in performance of tribological properties.