磁粉检测磁化电流计算与分析

Calculation and analysis of the magnetic current in the magnetic particle testing

铁磁性金属的磁感应强度达到饱和值的80%左右时,其表面缺陷的漏磁场将迅速增加。贴于被检金属表面的灵敏度试片仅提供一个金属表面处空间切向磁场强度大小的指示,不能用来准确验证被检工件是否已被充分磁化。针对周向磁化、纵向磁化、近体导体磁化、触头磁化和磁轭磁化等磁粉检测磁化方法的磁场分布特征,依照ISO 9934或ASTM E1444标准,计算和分析实现高灵敏度检测的磁化电流强度。

When the magnetic induction intensity of the ferromagnetic metal reaches the 80% of the saturated value, the surface defects of leakage magnetic field will increase rapidly. The sensitivity test piece on the surface of the tested metal only provides the tangential magnetic field strength of the metal surface, and cannot be used to accurately verify wheth- er the tested workpiece has been fully magnetized. Based on the magnetic field distribution characteristics of the circum- ferential magnetization method, longitudinal magnetization method, adjacent conductor method, prods current flow method and magnetic yoke method, in accordance with the ISO 9934 or ASTM E1444 standards, the high sensitivity de- tection of the magnetizing current strength is realized by the calculation and analysis.