n.去磁作用(退磁作用；祛磁效应)
It shows hard , strong magnetism , stable temperature , uneasy demagnetisation and well anti-causticity .It is widely used in stationeties, motors, speakes and metal detectors, etc. 其材质特点是硬而脆，磁性较强，温度稳定性好，不宜退磁，耐腐蚀性好。
