雷电流作用下铁件剩磁量的规律分析

剩磁法是一种雷灾鉴定中判定是否发生雷击事故的方法，但标准中只给出判定的参考剩磁数据，其数据通用性有待斟酌。为了探究铁件剩磁量的规律，通过模拟雷电流的发生，选取一定的试样进行冲击测试后测量剩磁，得出了影响剩磁的主要因素有铁件材质、尺寸、所在位置、测量位置、雷电流大小、冲击条件、次数等，并得出0.5~1.5 mT区间的数据同样可以作为判定依据。而当冲击次数为5次以后，由于铁件的剩磁累积效应，铁件的剩磁量逐步达到饱和。得到的结论为雷灾鉴定工作提供了一定的理论基础。

Regularities analysis of the recidual magnetic of the iron casting under the lightning current

Recidual magnetic method is an important method in lightning calamity investigation which can determine whether lightning accident occurred, but the standard only provided the reference data of the recidual magnetic, the generality of the data must be considered again. In order to explore the regularity of the recidual magnetic of the iron casting, it chose some samples to make impulse test by simulating the occurrence of the lightning current, then measured the recidual magnetic and showed that the main factors which influence the recidual magnetic include the material, the size, the position of the iron casting, the position of the measurement, the amplitude of the lightning current, the impact condition, and the impact times. The results show that the data from 0.5mT to 1.5mT can also be the basis. And because of the cumulative effect by the iron casting, the recidual magnetic tends to be saturated after 5 times of the impact. It also provides a theoretical basis for lightning calamity investigation.