Stress-dependent magnetoimpedance in Co-based amorphous wires with induced axial anisotropy for tunable microwave composites

Détection d'endommagement dans les composites fibres/résine à l'aide de la technologie micro-onde

“…Le milieu à expertiser est placé entre les deux antennes. Le champ émis traverse le milieu et l'onde transmise est récupérée et analysée par l'antenne émettrice ( (Sandacci et al, 2005)...). Les méthodes avec contact les plus fréquemment utilisées placent le milieu à expertiser soit à l'extrémité d'un guide d'onde, soit dans une structure propagative coaxiale dans lequel il joue le rôle de l'isolant.…”

“…Analyse des mesures micro-ondes et mise en corrélation avec le phénomène de rupture des fibres L'existence d'un champ de contrainte au sein d'un milieu influence ses proprié-tés diélectriques (Sandacci et al, 2005). Ici, le phénomène est mis en évidence par les mesures de l'amplitude du coefficient de réflexion pour l'éprouvette sous et hors charge ( figure 7).…”

Liquid pressure wireless sensor based on magnetostrictive microwires for applications in cardiovascular localized diagnostic

“…[8][9][10] While the metallic core provides the magnetic behavior, the cover has a protective and stress-inducting function. Due to its tiny dimensions and its particular effects like Giant Magnetoimpedance (GMI), [11][12][13][14][15][16][17] bistability, 18 ferromagnetic resonance 19 and magnetoelasticity, 20 these materials have been considered as promising sensor elements. Furthermore, since the metallic core is covered by a biocompatible pyrex shell, they are suitable for biological and medical applications.…”

Stress and field contactless sensor based on the scattering of electromagnetic waves by a single ferromagnetic microwire

“…While the metallic core provides the magnetic behavior, the cover has a protective and stress-inducting function. Due to its tiny dimensions and its particular effects like Giant Magnetoimpedance (GMI), [8][9][10][11][12][13][14] bistability, 15 ferromagnetic resonance, 16 and magnetoelastic resonance, these materials have been considered as promising sensor elements. Furthermore, since the metallic core is covered by a biocompatible Pyrex shell, they are suitable for biological and medical applications.…”

“…This change might be further enhanced with suitable annealing of the microwire. 10,25 It is also interesting to note that for driving field frequencies corresponding to magnetoelastic or ferromagnetic resonance frequencies of microwires, small variations of the applied field or stress can give rise to strong changes in permeability. In order to increase the sensitivity of the system, it is also important to select the frequency in that range for which the couple of antennas are close to resonance in wires.…”