Carbide Twist Drill Spiral Groove Abrasive Flow Polishing and Abrasive Flow Analysis

Abstract

In this paper, the abrasive flow polishing experiment for the spiral groove of twist drill as well as the flow simulation was carried out. CFD analysis was carried out for the abrasive flow in the spiral groove during the polishing of a twist drill by abrasive grain flow using FLUENT software. In order to obtain the state parameters of dynamic pressure and abrasive velocity in the flow channel, and to analyze their effects on the flow of abrasive and polishing result in the spiral groove, the CFD simulation calculations were carried out with different inlet velocities and abrasive grain concentrations respectively. The analysis results show that the dynamic pressure in the spiral groove of the twist drill increases with an increase in inlet speed, the pressure decreases as the abrasive flows along the spiral surface. Under the condition of different abrasive concentration, the velocity of abrasive decreases gradually with the increase of abrasive concentration. Under the same abrasive concentration condition, the abrasive velocity decreases gradually from inlet to outlet. For actual polishing, 50-60% abrasive concentration was suggested. In this research, the parameters of polishing process were set based on the simulation analysis results, experiment was designed adopting orthogonal test method the test data were analyzed using polar analysis method. Results showed that the priority order of the influencing factors of spiral groove polishing was: abrasive type > inlet flow velocity > polishing time. In addition, the inlet velocity of SiC abrasive was set to 0.5 m.s -1 , and polishing for 30 min. After polishing under these parameters, the surface roughness of cemented carbide twists drill spiral groove is the smallest, only Ra 0.189 µm, which is far less than the design requirements.