Influence of Sample Position on Strain Monitoring in Composite Materials Using Magnetic Microwires

Soft magnetic materials are highly suitable for use as sensors in the monitoring of materials, applications, and processes, with proven effectiveness across various industries. Their ability to be configured as microwires allows excellent integration within composite structures, making them particularly effective for structural health monitoring. Research in this area has enabled the analysis of both hysteresis loops and scattering parameters in transmission and reflection within the microwave frequency range, under conditions such as composite matrix polymerization or when subjecting specimens to different stress states. Consequently, a clear dependence of scattering parameters and impedance on applied stress in composites with magnetic microwire inclusions, which can be monitored, has been demonstrated. However, despite the repeatability of the phenomenon, modeling this behavior is challenging due to the dispersion of results caused by multiple factors and varying conditions that influence outcomes in a conventional environment. This study analyzes the influence of the relative sample position on these measurements and presents results obtained by modifying the position and orientation of microwires through rotation and flipping movements of the test specimen.