Study on process of removing burrs from group holes in TC4 titanium alloy plate by non-synchronous rotation grinding

It is crucial to remove the entrance and exit burrs of group holes in the TC4 titanium alloy plate. To improve the efficiency, a novel magnetic abrasive finishing (MAF) method by non-synchronous rotation of opposite magnetic poles is proposed to removing burrs. The influence of force change on the abrasives, magnetic field intensity, and magnetic field gradient on the burr removal under the relative rotation angle was studied. Meanwhile, the parameters are optimized through the experiment of non-synchronous rotation, which are magnetic pole speed, abrasives size, and abrasives filling amount by response surface methodology (RSM). By using the method of non-synchronous rotation, the constant magnetic field distribution is improved, and the renewal of the cutting edge of magnetic abrasives is accelerated. Based on the investigation of rotating grinding of opposite four magnets, when the rotation speed of magnetic pole I is 600 r/min, the best process parameters are obtained as follows: the rotating speed of magnetic pole II is 800 r/min, and the abrasives size is 250 μm, and abrasives filling amount is 30 g. The exit burr height decreased from 200.4 to 14.5 µm by 92.7%, and the entrance burr height decreased from 180.5 to 10.5 µm by 94.2%. The analysis of the experiment results shows that the relative speed of the magnetic pole is faster, the splashing of abrasives is easier, and the lower grinding efficiency. On the contrary, if the relative speed is smaller, the burr removal will be more difficult. However, the impact of the abrasives size and the abrasives filling amount on the burr height is insignificant. In the process of non-synchronous rotation grinding, the entrance and exit burrs are removed at the same time, so the removal amount is greatly increased, and the grinding efficiency is improved. According to numerical simulation and experimental analysis, non-synchronous rotation grinding process is verified, which provides a theoretical basis for the burr removal process.