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چکیده
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Ultra-precise finishing of parts with complicated geometry has faced many limitations using traditional methods due to the use of rigid tools. This study aims to introduce a new mechanism by developing a rotational abrasive finishing (RAF) operation, where the simultaneous rotation mechanism of a workpiece and the stirring-chamber is used in the opposite directions. In this paper, the associated velocities and forces in the developed RAF technique, the effects of stirring blades rotary speed, working gap as well as various meshing of abrasive grits on material removal (Δm), surface roughness variation rate (ΔRa) the percentage of surface improvement (%ΔRa), and the surface roughness value (Ra), on one of the most important cutting tools, i.e. drill bit, were examined. The research outcomes demonstrated that with increasing the speed of the stirring-chamber combined with the selecting larger abrasive grits, Δm and ΔRa will increase, while an increment in working gap resulted in a decrease in Δm and ΔRa. Also, reducing surface roughness from micrometer scale to nanometer (from initial value 547 nm to final value 69 nm) resulted in an 87% enhancement in the surface quality. Therefore, the superiority of RAF technique in ultrafinishing of various work parts can be demonstrated theoretically and experimentally
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