线锯切割中锯丝的高梯度磁场数值和理论分析

Numerical analysis and theoretical analysis in high gradient magnetic field based on wire of wire sawing

线锯切割常用锯丝——镀铜钢丝,作为一种聚磁材料,在匀强磁场中会被磁化产生高梯度磁场,对其附近的磁性磨粒产生磁力作用,使磨粒吸附在锯丝上,故在游离磨料线锯切割中添加辅助磁场,增加了切割区域内磨粒的数量,更有利于切割。为进一步研究锯丝产生的高梯度磁场,通过对辅助磁场与锯丝组成的磁系统进行数学建模,采用有限元的方法对整个系统进行数值模拟,发现辅助磁场的改变与产生的高梯度磁场的磁感应强度存在关系,即高梯度磁场的磁感应强度会随着永磁体之间距离的减小、永磁体宽度和高度的增大而变大。并通过理论计算与仿真结果的对比验证了仿真的正确性。

Copper coated steel wire is a kind of magnetism gathering material. It is widely used in free abrasive wire sawing. In uniform magnetic field, the wire is magnetized, then forms high gradient magnetic field. Because of the magnetism of the wire, many magnetic abrasives around the wire are adsorbed to the certain region of wire surface, which help to improve the cutting efficiency of wire saw. In order to study on the high gradient magnetic field of wire during wire sawing, the magnetic system, which consist of the auxiliary magnetic field and wire, was modeled. And the numerical simulation of the magnetic system was performed by FEM. The results show that, the magnetic induction intensity of high gradient magnetic field changes along with space geometric location of the permanent magnet, which is used as uniform magnetic field. And the validity of simulation results is validated by comparing the simulation results with the theoretical calculation.