铁磁材料在现代科学技术中得到广泛的应用，随着材料科学的发展，它已成为一种重要的智能材料。本文系统的研究了铁磁材料的力磁耦合行为，分别提出了细观和宏观本构模型。主要进行了以下方面的工作：1. 从细观力学的基本问题入手，分别用Green函数方法和等效夹杂方法推导了铁磁夹杂的基本解，并证明这两种方法是一致的。基于能量等效框架，得到一般压磁材料有效磁弹模量通解。通过双夹杂方法将超磁致伸缩复合材料中的力磁场解耦，成功预测了超磁致伸缩复合材料的等效弹性模量和等效饱和磁致伸缩，与现有其他模型比较最接近实验值。2. 自行设计和搭建了力磁耦合测量设备，并编写软件实现测量过程自动化。分别对金属软磁材料－Ni6和电解镍，超磁致伸缩材料－Terfenol-D，以及铁磁相变材料－NiMnGa单晶，进行了全面的力磁耦合实验，得到不同应力状态下磁滞回线，磁致伸缩曲线，不同磁场强度下应力应变曲线等特征曲线。利用磁畴理论，解释了实验现象。3. 基于磁畴理论，根据超磁致伸缩材料Terfenol-D的实验现象和磁畴旋转模型，发展了磁畴翻转模型。以Gibbs自由能作为磁畴翻转的判据。通过引入取向分布函数，可得到系统的宏观本构关系。4. 宏观上，铁磁材料的响应与加载历史相关，存在能量耗散，与经典塑性理论类比，基于热力学框架，发展了两类唯象本构模型：（1）类比于J2流动理论，将剩余应变和剩余磁化强度作为内变量，引入力磁耦合屈服面，推导出基于流动理论的唯象本构；（2）根据Karafillis-Boyce的多晶各向异性塑性理论，提出具有一般意义的非二次方的力磁耦合屈服面，使之适合于各向异性材料。其中，各向异性包括磁各向异性和弹塑性各向异性。利用特殊的线性变换，将各向异性等价为各向同性处理，从而使该模型可以统一处理各向同性材料和各向异性材料。通过实验测量出Terfenol-D的力磁耦合屈服面，由Helmholtz自由能函数给出演化方程，从而构成完整的三维本构模型。理论计算结果很好的符合实验数据。

Ferromagnetic materials have been widely used in modern science and technology. With the development of material science, ferromagnetic materials have become the important functional materials. The magneto-mechanical coupling behaviour is studied systematically in this dissertation. The experiments of ferromagnetic materials were conducted, and mesoscopic and macroscopic constitutive models are developed, respectively. The work involved in the following aspects: 1. Based on the mesoscopic mechanics, two different analytical methods, the Green’s function method and the equivalent inclusion method, were employed to investigate the ferromagnetic inclusion and inhomogeniety problem. The results show that these two solutions are completely equivalent to each other. Based on the generalized Budiansky’s energy-equivalent framework, the general expressions of effective magneto-elastic moduli were obtained. Furthermore, by using the well-known double inclusion method, the magneto-mechanical fields in magnetostrictive composites were decoupled and the strain induced by magnetostriction in magnetostrictive particles was regarded as eigen-strain, then, the effective modulus and effective magnetostriction of the composites were obtained successfully. The theoretical results were compared with both experimental results and those calculated from other models, which shows that the proposed model is coincident well with the experimental results.2. A magnetomechanical-coupling testing setup was established by ourselves, which was controlled by an industrial PC. The software was programmed to monitor the testing process and deal with the acquired data. There are three kinds of ferromagnetic materials used to investigate the magneto-mechanical coupling behavior, such as the soft-ferromagnetic metal of Ni6 and electrolytic nickel, the giant-magnetostrictive material (Terfenol-D), and the ferromagnetic shape memory material (NiMnGa). The characteristic curves of ferromagnetic materials were measured, including the hysteresis loops and the magnetostriction curves under different compressive stress and stress-strain curves under different external magnetic fields. 3. Based on the domain theory, a domain-switching model was developed from the experimental results of Terfenol-D and domain rotation model. In the proposed model, only 900 switching occurs. Based on the Gibbs free energy, the criteria of domain switching are established to judge the state of ferromagnetic domains. Then the macroscopic constitutive relations could be obtained by introducing the orientation distribution function.4. The response of ferromagnetic materials is dependent on the loading history because of energy dissipation, which was similar to the classical plastic theory. Based on the thermodynamic framework, two kinds of phenomenological models were developed: (1) According to J2 flow theory, the remanent strain and the remanent magnetization are introduced as internal variables, then the magneto-mechanical yield surface is introduced to govern the evolution of the remanent strain and the remanent magnetization. Then the model based on the flow theory was constructed. (2) According to Karafillis-Boyce model of anisotropic plastic theory, the general constitutive model based on the internal variable theory has been developed for ferromagnetic and magnetostrictive materials. A non-quadratic magneto-mechanical yield surface is introduced for both isotropic and anisotropic materials. The anisotropy includes both magnetic anisotropy and elastic anisotropy, which can be described by introducing a set of irreducible tensorial state variables. The linear transformation from anisotropy to isotropy is presented. Then, the proposed model is generalized for both isotropic materials and anisotropic materials. Furthermore, the magneto-mechanical yield surface of magnetostrictive material Terfenol-D was measured and the magneto-mechanical hardening moduli can be determined by Helmholtz free energy. The calculated results are consistent with the experimental data well.