Novel Magnetic Shape Memory Alloy Thin Films for Sensor and Actuator Applications

该奖项的研究目标是研究新型磁性形状记忆合金薄膜，并将这些薄膜用作传感器和执行器的骨干。特别是，一类新型的镍基Heusler合金薄膜，由于塞曼能量诱导相变，能够提供高频率响应和高驱动应变，将被用作模型系统并进行实际应用测试。这一目标将通过以下科学方法实现：(1)研究相偏析对相变的影响；(2)探索和调整薄膜中的残余应力以调整相变；(3)了解尺寸对场致应变和可逆相变的影响；(4)展示了通过双层膜进行磁场传感的概念；(5)通过膜制造执行器。如果成功，这项研究的好处将包括阐明场诱导形状在多个长度尺度上变化的基本磁微结构机制，以及用于传感器和执行器应用的新型磁形状记忆合金薄膜。该项目将显著改进能够快速可逆变形、阻尼和被动发电的主动传感系统的设计。其次，它将促进以磁性薄膜为重点的本地学习环境。活动将包括创建活跃材料的教学模块，通过？获得博士学位的途径？德克萨斯农工大学的奖学金项目，7-12年级的纳米材料实验室示范模型，以及本科生研究人员的参与。第三，通过现有的用户项目与集成纳米技术中心、洛斯阿拉莫斯国家实验室和桑迪亚国家实验室的科学家合作，将为研究生提供在这些先进的研究中心和实验室工作的机会。

The research objective of this award is to investigate novel magnetic shape memory alloy thin films and use these films as the backbone of sensors and actuators. In particular, a class of novel Ni-based Heusler alloy films, which is capable of delivering high frequency response as well as high actuation strain due to Zeeman energy induced phase transformations, will be used as a model system and tested for real applications. This objective will be achieved by using the following scientific approaches: (1) investigate the influence of phase segregation on phase transformations; (2) explore and tailor residual stress in films to tune phase transformations; (3) understand the size effect on field induced strain and reversible phase transformations; (4) demonstrate the concept of magnetic field sensing via bilayer films; and (5) fabricate actuators via membranes. If successful, the benefits of this research will include elucidation of fundamental magneto-microstructural mechanisms of field-induced shape change across multiple length scales, and a new class of magnetic shape memory alloy films for sensor and actuator applications. The project will significantly improve the design of active sensing systems capable of fast and reversible deformation, damping and passive power generation. Second, it will promote a local learning environment focusing on magnetic thin films. Activities will include creation of teaching modules of active materials, involvement of underrepresented groups through the ?Pathway to Ph.D.? fellowship program at Texas A&M University, laboratory demonstration models in nanomaterials for grades 7-12, and involvement of undergraduate researchers. Third, collaborations with scientists at the Center for Integrated Nanotechnologies, at Los Alamos National Laboratory and Sandia National Laboratory through the existing user project will provide graduate student opportunities to work at these advanced research centers and laboratories.