Institut für Experimentelle und Angewandte Physik, Christian-Albrechts-Universität zu Kiel , Olshausenstr. 40, 24098 Kiel, Germany.
Institute of Materials Research, Helmholtz Zentrum Geesthacht , Max-Planck-Straße 1, 21502 Geesthacht, Germany.
ACS Appl Mater Interfaces. 2017 Aug 2;9(30):25571-25577. doi: 10.1021/acsami.6b15598. Epub 2017 Jul 19.
The intrinsic strain at coupled components in magnetoelectric composites plays an important role for the properties and function of these materials. In this in situ X-ray nanodiffraction experiment, the coating-induced as well as the magnetic-field-induced strain at the coupled interface of complex magnetoelectric microcomposites were investigated. These consist of piezoelectric ZnO microrods coated with an amorphous layer of magnetostrictive (FeCo)SiB. While the intrinsic strain is in the range of 10, the magnetic-field-induced strain is within 10, one order of magnitude smaller. Additionally, the strain relaxation distance of around 5 μm for both kinds of strain superposes indicating a correlation. The value of both intrinsic and magnetic-field-induced strain can be manipulated by the diameter of the rodlike composite. The intrinsic interface strain within the ZnO increases exponentially by decreasing the rod diameter while the magnetic-field-induced strain increases linearly within the given range. This study shows that miniaturizing has a huge impact on magnetoelectric composite properties, resulting in a strongly enhanced strain field and magnetic response.
在磁电复合材料中，耦合组件的固有应变对于这些材料的性能和功能起着重要作用。在这项原位 X 射线纳米衍射实验中，研究了复杂磁电微复合材料耦合界面处的涂层诱导应变和磁场诱导应变。这些复合材料由涂有非晶磁致伸缩（FeCo）SiB 层的压电 ZnO 微棒组成。虽然固有应变为 10 左右，磁场诱导应变为 10 左右，相差一个数量级，但应变松弛距离约为 5 μm，两者的应变叠加表明存在相关性。这两种应变的大小都可以通过棒状复合材料的直径来控制。随着棒直径的减小，ZnO 中的固有界面应变呈指数增长，而在给定范围内，磁场诱导应变呈线性增长。这项研究表明，小型化对磁电复合材料性能有巨大影响，导致应变场和磁响应得到显著增强。
