铁磁材料应力损伤处弱磁信号的定量化研究

Quantitative Study of Weak Magnetic Signal at Stress Damage of Ferromagnetic Materials

弱磁应力检测技术可以实现对铁磁材料应力损伤的有效检测。然而由于弱磁信号形成机理复杂,很难实现定量化计算分析。文中基于铁磁材料形成静磁场的磁电耦合特性,建立了弱磁应力检测数学模型,计算了地磁场下弱磁信号在不同分量的磁力学特性及磁传递特性。研究结果表明地磁场对检测信号的影响随应力增加逐渐减弱;弱磁信号切向峰值与法向零点与应力损伤中心位置重合;弱磁信号随应力增加呈线性增加,随传播距离增加呈指数衰减;“线性区”弱磁信号识别效率高。

Weak magnetic stress detection technology can identify the stress concentration zone.However,the complex formation mechanism of the weak magnetic signal makes quantitative calculations and analyses very difficult.In this paper,based on the magnetoelectric coupling characteristics in the static magnetic field formed by ferromagnetic materials,a mathematical model for weak magnetic stress detection was established.The magneto-mechanical characteristics and magnetic transfer characteristics of weak magnetic signals of different components were analyzed.Study results show that the geomagnetic field s influence gradually weakens as the stress value increases.The tangential component peak value and the normal component zero-crossing point coincide with the center of the stress concentration zone.The weak magnetic signal increases linearly with stress level increases,and decays exponentially with propagation distance increases.The“linear zone”has a high signal acquisition rate for weak magnetic signals.