Magnetic field induced strain materials are classically represented by Giant Magnetostrictive Materials (GMM) such as Tb-Dy-Fe alloys offering magnetostrain of 0.1-0.2%. This family of smart materials has been extended for some years by cryogenic magnetostrictive materials such as Td-Dy and (Tb1-xDyx)Zn offering magnetostrain of 0.2- 1%. Even more recently, it has been completed by new Magnetic Shape Memory Materials (MSM) such as Ni-MnGa offering magnetostrain of 2-6%. These materials have lead to quite various large stroke and large force actuators. Some of these actuators meet the requirements of applications in different fields such as space or machine tools. The object of this paper is to review the present situation and recent progresses in the field of magnetic field induced strain materials, actuators, modelling and applications, including commercial aspects.
Piezoelectric actuators are generally deemed good candidates for driving compact and efficient mechanisms, offering advantages like fine precision, fast time response, low power consumption, cost annd easier implementation. But to meet space, devices have to comply to many other requirements besides functional ones.
Amplified Piezo Actuators have been developed at CEDRAT TECHNOLOGIES for several years. Their well – known advantages (rapid response and precise positioning) have been used in valve designs to obtain both rapid or fine proportional valves.
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