The coupling of magnetostriction and magnetoresistance in elastic ferromagnetic composites with conducting matrix

An elastic ferromagnetic composite with a conducting matrix is described. The composite consists of silicon steel particles of size 150–200 μm and graphite particles of size not exceeding 0.5 μm dispersed in polymerized silicone. The resistivity of the composite amounted to (8.32–0.28)×10−3 Ω m and depended on its chemical constitution. The structure of the system with a variable capacitance capacitor for a simultaneous measurement of magnetostriction and magnetoresistance of the produced composite is also described. The measurements were carried out in a magnetic field with induction amounting to 0–8 T generated by a Bitter type magnet. It was found that in a field with induction of 8 T the composite exhibits, depending on its chemical composition, longitudinal magnetostriction (0.14–0.80)×10−2 and relative longitudinal magnetoresistance 21.5–37.5%. After switching off the field, a hysteresis of magnetostriction of (0.03–0.13)×10−2 and a hysteresis of magnetoresistance of 6–14% was observed.