A piezomagnetic composite material force-sensitive film with high force-sensitive properties

Abstract Piezomagnetic sensor is a subject undergoing intense study. In this paper, a force-sensitive composite film with two layers was designed, and the force-sensitive properties of the film at σ ≤ 0.2 MPa was studied by inductance measurement. The composite film with a complex force-sensing mechanism can correct the fluctuations in the initial stage of the force-sensitive curve and improve the stability of the force sensitivity at the initial stage. Compared to the force-sensitive properties of Fe78Si13B9 amorphous alloy film, the composite film’s is significantly higher. When the thickness of the composite film is 180–250 μm, the film has high force-sensitive properties in the compressive stress interval of 0–0.1 MPa, the force-sensitive curve in the sensitive interval is linear approximation. When the thickness of the composite film is 200 μm and the test frequency f = 1 KHz, the sensitivity of the pressure sensor is as high as 0.27 μH/KPa in a wide pressure interval (0 ~ 0.06 MPa). When the thickness of the composite film is 230 μm and the test frequency is 1 KHz, the sensitivity of the pressure sensor is as high as 0.59 μH/KPa in a wide pressure interval (0 ~ 0.02 MPa). The force-sensitive film is the most stable and sensitive one among the current piezomagnetic force-sensitive films. In addition, it has broad application prospects.