磁性应力监测中力磁耦合特征及关键影响因素分析

Analysis of characteristics and key influencing factors in magnetomechanical behavior for cable stress monitoring

针对磁性应力监测研究中力磁耦合关系有多种变化趋势且一直没有合理理论解释这一问题,从磁性材料的微观磁畴运动出发,根据磁致磁化过程,详细分析了两种不同磁化状态下力致磁化的变化规律,揭示出力磁耦合关系的变化特征,进而提出磁化状态是导致力磁耦合关系差异的本质因素;对工程上实际缆索用镀锌钢丝在不同磁化状态下进行了力磁耦合试验,结果与理论一致:力磁耦合关系随磁化状态的不同而不同,本质上有效地解释了已有研究中力磁耦合关系的矛盾多样性.

Until recently the magnetomechanical behavior has been rather poorly understood with contradictory results and interpretations from different investigators in the study of stress monitoring by magnetic method. Based on the domain motion and field-induced magnetization process of magnetic material, the stress-induced magnetization process in two different magnetization states is analyzed in detail. Characteristics of the magnetomechanical behavior are revealed. Domain motion caused by stress always makes materials tend to stable state of free energy minimum and accordingly the magnetization will approach the anhysterestic magnetization. More- over, it can be concluded that magnetization state is an essential factor influencing the magnetomechanical behavior. Experiments of magnetomechanical behavior for galvanized steel wire have been conducted for different magnetization state, and the results are in accord with the theoretical analyses. The magnetomechanical behavior is changed with magnetization state, which can be effectively used to explain the existing complex and diverse research results.