某型船钢拉应力与磁场关系试验

Experimental study on relationship between tension stress and magnetic field for a type of ship steel

舰船磁场包括固定磁场和感应磁场,固定磁场是现有消磁勤务的主要目标。通过对船钢的拉伸试验,在船钢弹性形变范围内,研究其总磁场强度随拉应力的变化关系。由试验结果确定船钢的磁场强度初次发生显著变化时的拉力幅值。施力之前,通过试验从船钢的原始磁场中分离出感应磁场,然后任意选择一船钢总磁场发生显著变化的状态,在同样条件下做感应磁场分离试验。发现受力前后,感应磁场没有发生变化,即材料的磁导率回复到原始状态,总磁场的变化即固定磁场的变化。

A ship′s magnetic field is composed of the permanent magnetic field and the induced magnetic field.The permanent magnetic field is the primary objective in ship degaussing at present.The relationship between magnetic strength and tension stress on a type of ship steel was studied by tension experiments in the range of elastic deformation.The experiment results determined stress amplitude which appeared at a time when magnetic strength first changed remarkably.The induced magne-tic field could be separated from the original field by experiment before stress.The experiment was reduplicated under the same conditions when magnetic strength varied remarkably.The experiment results show that there is no change in the induced magnetic field and permeability of specimen before and after stress.The fact that the change in the total field is just that in the permanent field can be observed.