The dynamics of the magnetization reversal by means of head‐to‐head domain‐wall propagation is investigated both experimentally and theoretically for magnetic labels made from Fe‐rich bistable glass‐coated microwires. It is shown that the amplitudes of the electromagnetic harmonics generated by bistable Fe‐rich magnetic labels of the length 1–4 cm with metallic nuclear diameter of 10–20 µm are more than 5 times larger than that of similar labels made of Co‐rich microwires having high permeability and low coercive force. The electromagnetic harmonics can be detected at the distances up to 15–20 cm from the magnetic label at the signal‐to‐noise ratio not lower than 2.0.

Vibrational magnetometry and small‐angle magnetization rotation methods have been used to study magnetoelastic properties of glass‐coated Co‐rich microwires of composition Co69Fe4Cr4Si12B11 with metallic nucleus diameter d = 55 μm and total diameter D = 80 μm. The saturation wire magnetization has been found to be Ms = 590 emu cm−3, the magnetostriction constant λs = −0.49 × 10−7, and the bare anisotropy field Ha = 0.24 Oe. The average value of the residual quenching stress has been estimated to be Δσ ≈ 137 MPa. The diagonal Zφφ component of the giant magnetoimpedance tensor turns out to be significantly dependent on the position along the wire axis. This can be attributed to a non uniformity of the residual stress distribution. It is shown that the measurement of the magnetic characteristics of the microwire enables one to estimate quantitatively the magnitude of the applied mechanical stress.

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