Microactuator Systems Based on Epitaxial Ni-Mn-Ga Films with Magnetic Shape Memory Effect (EPITACT)

体磁形状记忆（MSM）合金，如Ni-Mn-Ga单晶，在中等磁场下可达到高达10%的高应变。在一个联合项目中，开发了基于MSM薄膜的新型集成微致动器系统。该子项目旨在生长具有适合微致动器的定制微观结构的外延Ni-Mn-Ga薄膜。薄膜将从衬底上释放出来，以获得显着的MSM效果。研究了沉积条件（成分、热处理、衬底、缓冲液、沉积速率等）对相形成、微观结构（织构、晶粒尺寸、缺陷）和磁性/磁弹性性能的影响。用这些薄膜来研究薄膜中MSM效应与体膜的差异。

Bulk magnetic shape memory (MSM) alloys like Ni-Mn-Ga single crystals reach high strains up to 10 % in a moderate magnetic field. In a joint project novel integrated micro actuator systems based on MSM films are developed. This sub-project aims at the growth of epitaxial Ni-Mn-Ga films with a tailored microstructure suitable for micro actuators. Films will be released from the substrate to obtain a significant MSM effect. The influence of the deposition conditions (composition, thermal treatment, substrate, buffer, deposition rate etc.) on phase formation, microstructure (texture, grain size, defects) and the resulting magnetic / magnetoelastic properties are examined. These films are used to study the difference of the MSM effect in thin films compared to bulk.