首先叙述了由单个轴向磁化环所产生的磁场 ,并就两个永磁环所产生的纵向磁场进行了分析 .对于两个沿同一方向磁化的永磁体环 ,沿磁环中心线将会产生一个强度较为均匀的轴向磁场 .如果两者的磁化方向相反 ,则在两磁铁间的区域将产生一个纵向的梯度磁场 ,其磁场强度介于-B0 到 +B0 之间 .设计制造了一个高梯度的轴向磁场 ,其磁场梯度为 4 7.2T m ,测量结果与计算结果非常一致 .文中还讨论了产生变梯度磁场的方法 .由于永磁环所产生的磁场和螺线管的磁场较为相似 ,磁铁外部空间将有较大的漏场 ,最后还讨论了屏蔽漏场的问题 First, the magnetic field generated by a single axial magnetizing ring is described and the longitudinal magnetic field generated by the two permanent magnet rings is analyzed. For two permanent magnet rings magnetized in the same direction, they will be generated along the center of the ring A more uniform axial magnetic field.If both are magnetized in the opposite direction, a longitudinal gradient magnetic field will be generated in the area between the two magnets with a magnetic field strength between -B0 and + B0 .A high Gradient axial magnetic field, the magnetic field gradient of 4. 7.2T m, the measured results and calculated results are very consistent.This paper also discusses the method of generating gradient magnetic field.As the permanent magnet ring magnetic field generated by the solenoid and the magnetic field is more similar , The magnet outer space will have a larger leakage field, finally also discussed the problem of shielding leakage field