利用磁性复合流体轮对管材外表面进行超精密抛光

Ultra-precision Polishing of Outer Surface of Tube Using Magnetic Compound Fluid Wheel

摘要:

提出了一种采用磁性复合流体（MCF）轮对不锈钢管外表面进行抛光的新方法。首先，构建了抛光装置，并通过Maxwell软件和特斯拉计探讨了MCF轮在工件表面的磁场分布，研究了磁场分布与工件表面材料去除（MR）之间的关系。然后，建立了MR模型，并通过给定条件下的实验结果验证了该模型。最后，通过实验研究了羰基铁粉粒径d_CIP、磨料粒径d_AP、磁铁转速n_m、工件转速n_c以及MCF供给量V对表面粗糙度R_a和减少率的影响规律，并探讨了不同参数对表面质量的作用机制。结果表明，抛光过程中的磁感应强度与工件的抛光轮廓呈正相关。MR仿真的趋势与实验值一致，证明了MR模型的准确性。在磁铁转速n_m=200 r/min和工件转速n_c= 5000 r/min条件下，使用含有50wt%羰基铁粉（15 μm）、12wt%磨料颗粒（7 μm）、3wt% α-纤维和35wt%磁性液体的MCF浆料（V= 2 mL），不锈钢管的表面粗糙度从0.411 μm降低到0.007 μm，抛光100分钟后，表面粗糙度的减少率达98.297%，证明了这种方法适用于管材外表面的抛光。

Abstract:

A novel method employing magnetic compound fluid (MCF) wheel was proposed for polishing the outer surface of stainless steel tube. Firstly, a polishing apparatus was constructed. In addition, the distribution of the magnetic field of MCF wheel on the workpiece surface was explored by Maxwell software and Tesla meter, and the relationship between magnetic field distribution and material removal (MR) on the workpiece surface was investigated. Then, MR model was established and proved by the experiment results under specific experiment conditions. Finally, the influence laws of carbonyl iron powder particle size d_CIP, abrasive particle size d_AP, magnet speed n_m, workpiece speed n_c, and MCF supply amount V on surface roughness R_a and reduction rate were investigated through experiments, and the mechanisms of different parameters on surface quality were explored. Results show that the magnetic induction intensity during polishing is positively correlated with the polished profile of the workpiece. The trend of MR simulation is consistent with that of the experiment value, which proves the accuracy of MR model. When the revolution speeds of magnet and workpiece are 200 and 5000 r/min, respectively, and 2 mL MCF slurry containing 50wt% carbonyl iron powder (15 μm), 12wt% abrasive particle (7 μm), 3wt% α-cellulose, and 35wt% magnetic fluid was used, the final surface roughness decreases from 0.411 μm to 0.007 μm. After polishing for 100 min, the reduction rate is 98.297%, demonstrating that this method is appropriate for polishing the outer surface of tube.