超磁致伸缩致动器各向异性磁滞损耗表征新方法

The hysteresis loss between input magnetic and output mechanical energies exists in the energy transformation process of giant magnetostrictive materials. In dynamic applications, hysteresis loss affects the amplitude of strain output, and restricts the effective power and miniaturization of the devices. The usual non-linear hysteresis models based on physics or mathematics are mostly complex in calculation and slow in response, limiting their application in dynamic control conditions of actuators.. Considering the requirements of giant magnetostrictive actuators to accurate and quick time-response hysteresis models in dynamic applications, this project proposes a novel method to characterize hysteresis loss by using magnetic, mechanical and magneto-elastic losses, which relates to magnetic, mechanical relaxation processes and anelastics. The three losses factors are reflecting in magnetic, mechanical and piezo-magnetic complex parameters from the constitutive equations. The key research content includes the following parts, establishing the relationship between the hysteresis losses factors and mechanical quality factors considering magnetic anisotropics, and the method of measuring losses factors; taking account of the eddy current losses model and the restricting method in structure; combining the hysteresis loss model with the giant magnetostrictive actuators itself, and verifying the consistency of equivalent circuit model with experimental results.. The research method will reveal the intrinsic origin of the material hysteresis loss, and offers a new approach for the analysis, design and control of actuator in dynamic applications.

超磁致伸缩材料的能量转换过程存在输入磁场能与输出机械能之间的磁滞损耗行为。在动态应用中，磁滞损耗影响系统的应变输出幅度，限制了器件有效功率及结构的小型化。常见的基于物理与数学的磁滞非线性模型计算复杂且响应较慢，使得模型在致动器动态控制应用中具有局限性。. 针对超磁致伸缩致动器动态应用对磁滞模型准确性与快速响应性的要求,课题提出了通过磁、机械与磁机耦合损耗来表征磁滞损耗的方法，涉及磁、机械弛豫过程及滞弹性行为，三种损耗因子体现在材料本构方程的磁、机械及磁机耦合系数的复变量形式中。关键研究内容包括建立考虑磁各向异性的磁滞损耗因子与机械品质因素之间的表达，损耗因子的实验测量方法；同时考虑动态涡流损耗模型及其结构性抑制方法；将磁滞损耗模型与超磁致伸缩器件进行耦合，及等效电路模型与实验的验证。. 研究方法揭示材料磁滞损耗本质来源，将为致动器动态应用的分析、设计提供新的途径。

超磁致伸缩材料的能量转换过程存在输入磁场能与输出机械能之间的磁滞损耗行为。在动态应用中，磁滞损耗影响系统的应变输出幅度，限制了器件有效功率及结构的小型化。常见的基于物理与数学的磁滞非线性模型计算复杂且响应较慢，使得模型在致动器动态控制应用中具有局限性。. 针对超磁致伸缩致动器动态应用对磁滞模型准确性与快速响应性的要求,课题提出了通过磁、机械与磁机耦合损耗来表征磁滞损耗的方法，涉及磁、机械弛豫过程及滞弹性行为，三种损耗因子体现在材料本构方程的磁、机械及磁机耦合系数的复变量形式中。关键研究内容包括建立考虑磁各向异性的磁滞损耗因子与机械品质因素之间的表达，损耗因子的实验测量方法；同时考虑动态涡流损耗模型及其结构性抑制方法；将磁滞损耗模型与超磁致伸缩器件进行耦合，及等效电路模型与实验的验证。. 研究方法揭示材料磁滞损耗本质来源，将为致动器动态应用的分析、设计提供新的途径。