旋转磁极辅助磁力研磨对TA18管内表面光整加工

Finishing of inner surface of TA18 pipe by rotating magnetic pole-assisted magnetic grinding

采用旋转磁极辅助磁力研磨加工技术对TA18管内表面进行光整加工。对比了旋转磁极辅助和单纯磁力研磨加工前后表面粗糙度的变化,探究了辅助磁极转速和管件转速对TA18管内表面粗糙度的影响。获得了如下较佳的工艺参数:辅助磁极转速1 500 r/min,管件转速1 000 r/min,进给速率2 mm/s。在上述工艺条件下对TA18合金管内表面研磨15 min,其表面粗糙度从原始的0.89μm降至0.12μm,表面的应力状态由原始的残余拉应力+169 MPa变为压应力-112 MPa,有效提高了工件的疲劳强度。

The inner surface of TA18 pipe was machined and finished by magnetic grinding with the assistance of a rotating magnetic pole. The variation of surface roughness before and after magnetic grinding with and without rotating magnetic pole assistance was compared. The effects of rotation rates of auxiliary magnetic pole and pipe on the inner surface roughness of TA18 pipe were studied. The optimal parameters were obtained as follows： rotation speed 1 500 r/min for auxiliary magnetic pole and 1 000 r/min for the pipe, and feeding rate 2 mm/s. The roughness of inner surface of TA 18 pipe is decreased from 0.89 μm previously to 0.12 μm after grinding under the optimal process conditions for 15 min. The surface stress is converted from tensile （＋169 MPa） to compressive （-112 MPa）, improving the fatigue strength of the pipe effectively.