Study of magnetization behavior of glass-coated amorphous ferromagnetic microwires

In this paper, two relevant problems are investigated. First, the residual stresses within glass-coated amorphous ferromagnetic microwires (AFMWs) subjected to thermal expansion mismatch and magnetostriction effect are analyzed using the finite element method; the effects of various design parameters (e.g., the thickness of the glass cover) on the residual stress are discussed as well. Then, based on the theory of micromagnetics, the magnetization states of AFMWs under the collective effects of stress and external axial magnetic field are analyzed. It has been found that the magnetization of AFMWs with negative saturation magnetostriction from -0.1 × 10^-6 to -0.3 × 10^-6 is sensitive to stress change, and external magnetic field of the proper amplitude can help to increase this sensitivity. This study should provide guidance on the optimal design of glass-coated AFMWs and their potential applications in tunable microwave composites and stress sensors.