Improvement of the Piezomagnetic Measurement and Characterization Method of Fe-based Amorphous Alloy Ribbons and Their Piezomagnetic Properties

A new improved test system was developed based on the non-contact inductance method, which can be used to characterize the piezomagnetic properties of Fe-based amorphous alloy ribbons properly. The studies show that when the test frequency is 1 kHz, the voltage is 0.3 V and the compressive stress σ ≤ 0.1 MPa, the amorphous magnetic material of Fe_73.5Cu₁Nb₃Si_13.5B₉ has excellent piezomagnetic properties, and its ribbons of different specifications exhibit perfect stability and repeatability after repeated experiments. The ribbons are extremely sensitive to tiny stress, and they show a rapidly rising trend of the inductance once the initial pressure is applied on the ribbons. Moreover, the further amplifying experiment indicates that the sensitivity range is 0∼1.5 kPa. In addition, the size of Fe_73.5Cu₁Nb₃Si_13.5B₉ ribbons influence significantly the piezomagnetic property, and the initial inductance and its corresponding S_I-Max value of the ribbons increase substantially along with the sample size increasing; with the same width, the piezomagnetic property is superior to others while the thickness is 33∼36 µm, and S_I-Max is 19.8%. With the same thickness, the ribbons with a width of 20 mm show an excellent piezomagnetic property and the S_I-Max has reached 22.02%.