以300目非晶Fe73Si1 8B9粉体为敏感组元,硅橡胶为基体,制得了粉体含量为25%,75%及83.3%(质量分数),厚度200μm复合薄膜;采用LYYL-500N高档型微机控制压力实验机对薄膜试样进行连续加载卸载实验,同时,使用TH2816LCR数字电桥采集薄膜在测试频率为1kHz,压应力加载速度分别为0.05,0.1和0.5mm/min条件下的阻抗值Z,研究了不同粉体含量的复合薄膜的力敏特性,比较了纳米晶FeCuNbSiB粉体/硅橡胶复合薄膜和非晶FeSiB粉体/硅橡胶复合薄膜力敏特性。研究表明,复合薄膜在连续加载/卸载速度≤0.1mm/min,测试频率1kHz、压应力0.03~1.0MPa时,具有良好的力敏稳定性和灵敏性。薄膜对于小于0.2 MPa应力更加灵敏,在此应力范围内,薄膜中粉体含量增加,薄膜的力敏特性变化趋势相同,但薄膜的力敏敏感度增大。当薄膜中粉体含量为83.3%(质量分数),压应力由0.03增大到0.2MPa时,在加载过程中薄膜的SI%由36.51%增大到82.48%,k值由42.91减小到1.889;当应力为0.2~0.7 MPa时,薄膜的k值在1.889~0.6之间,应力继续增大至1MPa时,k值逐渐接近0。
Composite film was prepared by amorphous Fe73Si18B9powder,300mesh,as sensitive phase and silicone rubber as matrix phase.The content of powder of film was 25wt%,75wt% and 83.3wt% and thickness was 200μm.The data of impedance-Z were collected by TH2816LCR digital bridge while the data of stress-σwere collected by LYYL-500Nhigh-grade type microcomputer control pressure testing machine when frequency was 1kHz and speeds of the continuous loading/unloading stress were 0.05,0.1and 0.5mm/min.The forcesensitive properties of the film were studied when stress loading and unloading was continuous in different speed and the force-sensitive properties were compared between FeCuNbSiB powder/silicone rubber composite film and FeSiB powder/silicone rubber composite film.The results show that when speed of continuous loading and unloading was less than 0.1mm/min in the stress range from 0.03to 1.0 MPa,composite film has excellent force-sensitive stability and sensitivity.When stress was no more than 0.2MPa,the film was more sensitive.With the content of the powder increasing,the variable trend of the force-sensitive properties was alike while the value of sensitivity-k was up.When stress was from 0.03to 0.2MPa,the value of SI% of film with the83.3wt% powder content was from 36.51% up to 82.48%,the value of sensitivity-k was from 42.91down to1.889.When stress was from 0.2to 0.7MPa,the value of kof film with the 83.3wt%powder content was between 1.889and 0.6.As the stress reaches 1MPa,the value of k gradually approaches to 0.