金属磁记忆效应的第一性原理计算与实验研究

First-principles caculation and experimental study of metal magnetic memory effects

为研究铁磁材料应力集中区域金属磁记忆信号的产生机理及其变化规律,采用基于密度泛函理论的第一性原理平面波赝势法,建立了磁记忆效应的磁力学模型;计算分析了力与磁记忆自发漏磁信号的定量变化关系.研究结果表明:力作用导致晶格畸变是磁记忆自发漏磁信号产生的根本原因;常温下,磁记忆信号随应力近似线性变化的规律与X70钢管水压爆破实验结果具有很好的一致性.研究结果有助于金属磁记忆检测机理的研究.

In order to investigate the mechanism and regular pattern of metal magnetic memory （MMM） signal, from the angle of electron spin, the magnetomechanical model of MMM is set up, and the relationship between stress concentration state and self magnetic flux leakage （SMFL） signal is calculated by the plane wave and pseudo-potential method based on the density functional theory. The research results show that the fundamental reason for SMFL is lattice distortion induced by loads, and the theoretical calculations are in very good agreement with the experimental observations. The present work is helpful for testing the mechanism of MMM.