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.