基于Hilbert曲线磁粒研磨轨迹均匀性实验研究  

Experimental Study on Magnetic Particle Grinding Uniformity Based on Hilbert Curve

作　　者：张志鹏 陈燕[1] 潘明诗 吴炫炫 高慧敏 ZHANG Zhi-peng;CHEN Yan;PAN Ming-shi;WU Xuan-xuan;GAO Hui-min(School of Mechanical Engineer and Automation,University of Science and Technology Liaoning,Liaoning Anshan 114051,China)

机构地区：[1]辽宁科技大学机械工程与自动化学院,辽宁鞍山114051

出　　处：《表面技术》2022年第8期408-417,共10页Surface Technology

基　　金：国家自然科学基金(51775258);辽宁省自然科学基金重点项目(20170540458);精密与特种加工教育部重点实验室基金(B201703)。

摘　　要：目的改善传统平面磁粒研磨中轨迹均匀性较差、材料去除不均匀等问题。方法首先,基于Hilbert分形曲线加工平面,对Hilbert分形曲线进行几何特征的修改,进一步改善研磨轨迹的均匀分布;其次,传统磁粒研磨平面时采用圆柱磁极,其半径方向线速度的差异会导致材料出现去除量不一致等问题,使用环形磁极进行研磨,对不同长径比环形磁极进行三维静磁场模拟仿真,对比不同长径比的磁感应强度和1 mm处的磁场强度曲线,选取最佳的长径比进行研磨,在一定程度上保证材料的均匀去除;最后,利用ADAMS软件进行单个磨粒运动轨迹的仿真,建立笛卡尔坐标网格划分,利用离散系数C_(v)进行轨迹密度的数值分析,对研磨轨迹均匀性进行评价。结果长径比为3∶4的环形磁极的磁感应强度最大,可达300 mT左右。在相同条件下,分别沿传统直线往复式路径、Hilbert曲线和改进的Hilbert曲线进行仿真,经离散系数C_(v)的评定,沿改进Hilbert曲线的研磨轨迹均匀性显著提高,离散系数C_(v)为0.407,较传统往复式的离散系数提高了约43.2%,较Hilbert曲线路径的离散系数提高了约10.7%。沿改进的Hilbert曲线的9个检测点的表面粗糙度降幅基本一致,降幅曲线平缓。原始表面的加工纹理、缺陷被完全去除,研磨后表面形貌均匀平坦。结论沿改进的Hilbert加工路径进行研磨,研磨轨迹复杂多样,且分布相对均匀,确保了表面材料去除量的均一性,表面质量较好。Planar magnetic particle grinding technology is a special processing technology that uses magnetic force to carry out mechanical grinding.With the development of science and technology,magnetic particle grinding technology is constantly applied to the processing of products in the such fields as high-precision machinery,instrumentation and aerospace,where the requirements for the machining accuracy and surface quality of workpieces are becoming more and more stringent.The surface quality of the workpiece,especially the grinding uniformity,is an important indicator to evaluate the quality of processing,and the uniformity of the grinding trajectory is directly related to the selection of the processing path.Thus far,in the planar magnetic particle grinding process,most of the traditional linear reciprocating processing path,this processing method exists in such issues as the workpiece surface can not be uniform grinding,grinding track repetitive,part of the grinding stripes easy to deepen.In response to these problems,the Hilbert curve is proposed as the grinding path,which is different from the traditional linear reciprocating type of planar magnetic particle grinding.This paper aims to optimize the geometrical features of the Hilbert fractal curve and compare the magnitude of magnetic induction at the end face of the toroidal pole with different length-to-diameter ratios to find the suitable pole size,and modify the geometrical features to improve the uneven distribution of the trajectory caused by the direct adoption of the Hilbert fractal curve.Under the same conditions,single grain grinding trajectories were simulated using ADAMS along the conventional linear reciprocating path,the Hilbert curve and the modified Hilbert curve,and the workpiece grid was divided to count the coordinate points of the grinding trajectories.The coefficient of dispersion is 0.407,with an improvement of approximately 43.2%compared to the conventional reciprocating type and approximately 10.7%compared to the Hilbert curve path.Secondl

关 键 词：磁粒研磨 研磨轨迹 Hilbert分形曲线 轨迹均匀性 磁场仿真 表面形貌 

分 类 号：TG356.28[金属学及工艺—金属压力加工]