以 Fe73.5 Cu1 Nb3 Si13.5 B9粉体为复合相,丁基橡胶为基体,制得粉体质量含量为80%、厚度为200μm的复合薄膜;采用 TH2816LCR 数字电桥测试频率1 kHz下薄膜的阻抗Z 随压应力σ的变化情况,用LYYL-500N高档型微机控制压力试验机对薄膜体系进行程序控制加载;薄膜体系采用电容方式连接。研究了复合薄膜在3种不同的压应力条件下连续加载/卸载的力敏特性。研究表明,复合薄膜在连续加载/卸载速度≤0.5 mm/min和保压加载/卸载条件下、测试频率1 kHz、压应力0.1~1.0 MPa 时,复合薄膜具有良好的力敏稳定性和灵敏性。随着应力σ增大,阻抗Z 呈非线性下降,SI%值为6%~23%,灵敏精度k=Z’(σ)值范围1.9~0.02,测试标准偏差稳定在0.02~0.01,薄膜对于〈0.3 MPa 应力更加灵敏。增加测试频率可以提高薄膜体系的力敏灵敏度。在压应力0.2~1.0 MPa范围内,薄膜弹性后效现象显著,导致薄膜加载Z-σ曲线与卸载曲线不重合。
The composite film was prepared by FeCuNbSiB powder as a compound phase and silicone rubber as a matrix phase.The content of powder was 80% and the thickness of film was 200μm.Impedance-Z and stress-σof film were tested by TH2816LCR digital bridge with frequency at 1 kHz.LYYL-500 N high-grade type mi-crocomputer control pressure testing machine was used to control loading.The 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 at 1 kHz and stress between 0.2 and 1.0 MPa,the compos-ite film has an excellent force-sensitive stability and sensitivity in condition that the speed of continuous loading and offloading speed was lower than 0.5 mm/mim with loading and unloading retentively.The impedance was declining nonlinear with the stress increasing.The value of SI% was 6%-23%,and the value of sensitivity k ranges from 1.9-0.02,the standard deviation was stability between 0.02 and 0.01.The film was more sensitive increasing test frequency can improve the sensitivity of film.When stress was between 0.2 and 1.0 MPa,the e-lastic aftereffect phenomenon was obviously,which leads to the loading Z-σcurve and unloading was not coinci-dent.