Magneto-optical Kerr microscope with in situ tension-compressionstage

所要求的克尔显微镜在跨学科研究活动中提供了广泛的应用可能性，用于研究磁畴结构、它们的分布以及它们随磁化强度、机械应力和温度的行为。重点研究了铁磁结构材料在机械应力和温度作用下的局部微磁特性。克尔显微镜系统是一种利用磁光克尔效应作为对比机制的高科技光学显微镜，用于可视化磁畴和磁化过程。该系统将主要用于探索磁化的微结构相关机制，以表征材料在弹性应力下的行为。虽然大多数建筑材料在远低于屈服强度的低载荷应力下工作，但由于缺乏关于塑性变形之前的机制的信息，对材料响应的准确表征是非常有限的。基于铁磁材料的磁参数分析，即使在低机械应力下，也可以量化材料的响应和与操作相关的微观结构变化。所提出的克尔显微镜的新颖实验配置允许高分辨率光学显微镜表征铁磁结构材料的磁畴，以及通过施加外加磁场、机械应力和温度来观察磁畴壁的运动。研究活动的目的是为观察、描述和确定材料行为机制创造新的基础，以探索材料科学和工程中的最新科学问题。该显微镜还将用于复合材料和轻金属的现场研究项目。申请人目前所有必要的变形行为研究项目都包括通过扫描电子显微镜和计算机层析成像进行现场力学测试。光学显微镜的位相对比度可以同时进行微观结构分析和裂纹扩展的观察，填补了多尺度原位表征变形和破坏机制的空白。可望，所提出的克尔显微镜的器件结构将为理解铁磁材料的弹性行为以及复合材料和轻金属的变形行为提供新的维度。因此，新型科尔显微镜将产生重要的洞察力，有助于从根本上理解材料的行为，特别是在低应力下，以最高的科学精度在原位进行探索。

The requested Kerr microscope offers a wide range of application possibilities in interdisciplinary research activities with regard to the investigation of magnetic domain structures, their distribution and their behavior in dependence of magnetization, mechanical stresses and temperature. The focus is on the characterization of the local micro-magnetic characteristics of ferromagnetic construction materials caused by mechanical stress and temperature.The Kerr microscope system is a high-tech light microscope using the magneto-optical Kerr effect as contrast mechanism for the visualization of magnetic domains and magnetization processes. The system will be mainly applied for exploring the microstructure-dependent mechanisms of magnetization in order to characterize material behavior under elastic stresses. Although most construction materials are operated under low load stresses far below the yield strength, an accurate characterization of material response is very limited by a lack of information about the mechanisms preceding a plastic deformation. Based on the analysis of magnetic parameter of ferromagnetic materials, it is possible to quantify the response of material and of the operationally relevant microstructural changes even at low mechanical stress. The novel experimental configuration of the proposed Kerr microscope allows a high-resolution light-microscopic characterization of the magnetic domains of ferromagnetic construction materials as well as the movement of the domain walls by applying of an external magnetic field, mechanical stresses and temperature. The aim of the research activities is to create new basis for observation, description and determination of mechanisms of material behavior in order to explore latest scientific issues in materials science and engineering. The microscope will also be applied in research projects for in situ investigation on composite materials and light metals. All current research projects of applicant on deformation behavior necessary include in situ mechanical testing by means of scanning electron microscopy and computer tomography. The phase contrast of light microscopy allows simultaneous microstructure analysis as well as observation of the crack propagation closing the gap in multiscale in situ characterization of deformation and failure mechanisms.It is expected, that the proposed device configuration of the Kerr microscope will provide new dimension in understanding of elastic behavior of ferromagnetic materials as well as deformation behavior of composites and light metals. Therefore, the novel Kerr microscope will generate a significant insight that will contribute to a fundamental understanding of the material behavior especially under low stresses, explored in situ with highest scientific precision.