Amorphous glass-coated microwires with positive magnetostriction are characterized by the magnetic bistability where the switching between the two stable magnetic states appears at the switching field. The switching field is sensitive to the external parameters like magnetic field, temperature, mechanical stress, etc., which gives us possibility to employ the microwires as a miniaturized sensing elements for the mentioned parameters.
Apart from this, there are many other advantages of microwires: the small dimensions (which allows them to be introduced inside various materials), glass-coating (that provides biocompatibility and protection against chemically aggressive environment), magnetic nature (for contactless sensing), simple production process (that allows very efficient production of large amount of wires in a short time), and many more favorable properties.
Within this chapter an overview of various parameters that affect the switching field of bistable microwires is given. Four different possibilities to use bistable microwires as sensors are shown: sensors of magnetic field, wide-range temperature sensors, selected temperature sensors for biomedical applications as well as stress sensor. At the end of each section, real applications of such sensors are demonstrated.
R. Varga, P. Klein, R. Sabol, K. Richter, R. Hudak, I. Polaček, D. Praslicka, M. Šmelko, J. Hudak, I. Mikita, G. A. Badini-Confalonieri, R. El Kammouni, and M. Vazquez