Magnetorheological (MR) fluid damper which allows the damping characteristics of the damper to be continuously controlled by varying the magnetic field is extensively used in metal cutting to suppress tool vibration. Even though magnetorhelogical fluids have been successful in reducing tool vibration, durability of magnetorhelogical fluids remains a major challenge in engineering sector. Temperature effect on the performance of magnetorhelogical fluids over a prolonged period of time is a major concern. In this paper, an attempt was made to reduce temperature and to improve viscosity of magnetorhelogical fluids by infusing nanoparticles along with MR fluids. Aluminium oxide and titanium oxide nanoparticles of 0.1% and 0.2% concentration by weight were considered and experimental tests were conducted to study the influence of nanoparticles on the performance of magnetorheological fluid. From the experimental results it was observed that the presence of nanoparticles in MR fluid reduces temperature and increases the viscosity of MR fluid thereby increasing the cutting performance during turning of hardened AISI 4340 steel.