同学们知道:地球是一个巨大的磁体,而水面舰艇和潜艇绝大多数是用钢质材料制成的,舰艇的主机、辅机和锅炉等设备也大多是钢质材料,这些钢质设备与材料均是良好的磁化物(硬磁材料),此时舰艇如果处于地磁场中就容易被磁化,并在其周围产生不同方向、强 The students know that the Earth is a huge magnet, while the vast majority of surface ships and submarines are made of steel materials. The main equipment, auxiliary engines, and boilers of ships are also mostly steel materials. These steel equipments are The materials are all good magnetic materials (hard magnetic materials). At this time, if the ship is in the earth’s magnetic field, it is easily magnetized and generates different directions and strength around it.