Force-sensitive properties of 83wt% FeCuNbSiB powder/silicone rubber composite film

Composite film was prepared by Fe73.5Cu1Nb3 Si13.5B9 powder as compound phase and silicone rubber as matrix phase. The content of powder was 83% and the thickness of film was 200μm. Impedance- Z and stress- σ of film were tested by TH2816LCR digital bridge when frequency was 1kHz. LYYL-500N high-grade type microcomputer control pressure testing machine was used to program control loading. Film system was connected by capacitance way, the force-sensitive properties were studied when stress loading and unloading was continuous or retentive. The results show that when frequency was 1kHz and stress was 0.2-1.0MPa, composite film has excellent force-sensitive stability and sensitivity in condition that the speed of continuous loading and unloading was low 0.5mm/mim and loading and unloading was retentive. The impedance was declining nonlinear with the stress was increasing. The value of SI% was 6%-23%, the value of sensitivity-k was 2-0.2, the standard deviation was stability in 0.02-0.05. The film was more sensitive when stress was low to 0.3MPa.Increasing test frequency can improve the sensitivity of film. When stress was between 0.2-1.0MPa the elastic aftereffect phenomenon was obvious, which leads to the loading Z-σ curve and unloading was not coincident.