The Property Of Giant Magnetostrictive Thin Film With Sensitive Layer And Its Application In Gas Detection

Gas sensitive sensor has been widely used in gas detection such as poisonous gas,burnable gas,greenhouse effect gas,industry exhaust gas and so on. As a new functional material, giant magnetostrictive thin film (GMF) with sensitive layer exhibits vast potential in the field of gas sensitive sensor, which can benefit from the large magnetostrictive strains, high energy density, short response time, non-contact driving, and easy integration and micromation. Based on this new functional material, one kind of gas sensor is designed. Through analyzing the static and dynamic characteristics of GMF with sensitive layer, a new way is provided to study GMF micro sensor and gas detection, with some new principles and methods.The magnetostrictive phenomenon and magnetostrictive principles are introduced. Meanwhile, the property of the material, its effecting elements and the vibration model of cantilever GMF are analyzed, which is fundamental for the sensor design. Then, one kind of positive and negative GMF with Cu substrate is prepared. Moreover, the surface quality and magnetic quality are researched.Aiming at the requirement of drive magnetic field, one Helmholtz coil is designed. Moreover, the power is optimally designed, and the magnetic uniformity of axis and radial is calculated and emulated by finite element analysis. In the experiment, high uniformity of the magnetic field is verified; meanwhile, the relationship between magnetic intensity and drive current is analyzed. Then the static and dynamic properties of GMF with sensitive layer are researched, which can be used for the further study of magnetostrictive devices.GMF is increasingly applied in the design of sensor for its many virtues. Acetic acid gas sensor is taken as an example. The principle of GMF sensor was introduced, and response curve of resonate frequency is established. The experiment verified that GMF is suitable for gas sensor for the detection of acetic acid with stable, swift and precise response.High uniformity and intensity drive magnetic field endow GMF with sensitive layer fine static and dynamic property, the result of which provides a new way to gas sensor and the application of GMF.