Permanent magnet systems with strong stray magnetic fields and very high gradients for material separation

摘要

The system consisting of permanent magnets of Kittel open domain structure with a mask made of thin sheets of soft magnetic material is described. The simulations showed that the maximal value of induction for system consisting of two neodymium- iron -boron magnets in presence of a mask is increased from 3 T (without a mask) up to 4 T. In this case the product B▽B on the distance of 0.01 mm achieves a value of 4.2 x 10~(11) mT~2/m. The experimental device with a mask made of low carbon steel sheets is shown to be useful for separation of paramagnetic substances such as dysprosium sulfate, europium chloride and copper chloride.