Magnetic behavior measurements under high frequency mechanical solicitations

The magnetic behavior under applied mechanical stress at audible and inaudible frequencies is investigated. A focus is given on how remanent induction, coercive field strength and permeability values that describe hysteresis-loop shape are involved. To this aim, an experimental setup is introduced to both measure mechanical and magnetic behaviors. The mechanical resonant modes of a magnetic ring core sample are tracked to allow large longitudinal bendings. It results that the coercive field strength and remanent induction are greatly reduced under these mechanical solicitations. Those results are then set forth to show that elastic mechanical applied stress is relevant to describe these effects for both steady and transient operating conditions. The experimental results are then focused on how specific magnetic losses and complex permeability spectra depend on the applied stress amplitude. These results are finally discussed to highlight future applicative developments.