A Master Dissertation from Lorena Engineering School (EEL)-USP aimed at finding new materials that can be used as sensors and actuators (elements that produce movement, from manual, electrical or mechanical commands). This Dissertation considered both the cost and magnetostrictive property of materials, in order to create a transducer for the tests. The magnetostriction is a physical phenomenon in which the materials are physically deformed (enlarging or contracting) with only the application of a magnetic field that interacts with the magnetic component of the atoms in the material, causing a separation or approaching of them.
Under the advising of Professor Cristina Bormio Nunes, the materials engineer Matthew Botani researched iron and aluminum alloys (Fe-Al) with the addition of the chemical element boron (B), which less costly and has potential for using in mobile equipments. In magnetostriction deformation values are small, around tens of parts per million. "Imagine that I apply a magnetic field in a bar in our [Fe-Al-B] material 100 meters long, the deformation would be around 7 mm", says Botani.
More information in Portuguese at : http://www.prpg.usp.br/index.php/pt-br/noticias/1216-engenheiros-desenvolvem-ligas-com-maior-deformacao-fisica
Source: Agência USP