定向凝固技术已经成功地应用于可加工S_m-C_o永磁体的制备并表现出工艺简单等优点。该技术中,易磁化轴的取向排列是利用基体相定向凝固形成的择优取向来实现的。这就要求基体相的择优生长方向必须与其易磁化方向平行;这是采用定向凝固技术制备永磁体的前提。对于NdFeB永磁合金,基体相Nd_2Fe_(14)B具有四方晶体结构,易磁化方 Directional solidification technology has been successfully applied to the manufacture of machinable S_m-C_o permanent magnets and shows the advantages of simple process. In this technique, the easy-to-magnetize axis alignment is achieved by utilizing the preferred orientation of the matrix phase solidification. This requires that the preferred growth direction of the matrix phase must be parallel to its easy magnetization direction; this is the premise of the directional solidification technology for the preparation of permanent magnets. For NdFeB permanent magnet alloys, the matrix phase Nd 2 Fe 14 B has a tetragonal crystal structure, easy magnetization