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以60~100 nm 的 FeNi 粉体为应力敏感元、硅橡胶为柔性基体,压制成型了粉体分布均匀、粉体含量30．6％(质量分数)、厚度200μm 的薄膜,在连续加载/卸载速度为0．1 mm/min、测试频率1 kHz 条件下,研究了正应力和综合应力两种受力条件下薄膜的力敏特性.研究结果表明,通过过渡溶剂液相混合方法可实现纳米级FeNi粉体在薄膜中均匀分布；在正应力条件下,加载过程中σ＜0．2 MP a 时,薄膜的灵敏精度|k|值＞50,当σ为0．2~0．4 MPa,|k|值介于37~49之间,薄膜对＜0．2 MPa的正应力敏感；当综合应力σ＜0．1 MPa 时,薄膜灵敏精度|k|值在60以上,薄膜对＜0．1 MP a的综合应力敏感；在综合应力加载/卸载条件下,薄膜的弹性后效现象显著,导致力敏稳定性较差；在正应力条件下的力敏特性优于综合应力条件下的力敏特性.

This article adopted 60-100 nm FeNi powder as the stress sensitive source,silicone rubber for flexible substrate,and prepared composite films which the powders were distributed uniformity,powder content was 30.6wt%,and whose thickness was 200 microns.And the film force sensitive features with normal stress and integrated stress conditions were studied,under the conditions that the continuous load/unload speed was 0.1 mm/min,and test frequency was 1 kHz.The study shows that Nanoscale FeNi powders are distributed evenly in the film through excessive solvent liquid phase mixing method.Under the condition of normal stress,the sensitive precision of the thin film,i.e-.|k|value was greater than 50 whenσ<0.2 MPa in the process of load-ing,while|k|value is between 37 and 49 whenσis 0.2-0.4 MPa.In hence,the film is sensitivity to the normal stress that is less than 0.2 MPa.Under the condition of comprehensive stress,the value of sensitive precision of the thin film is more than 60,and the film is sensitive to the comprehensive when it is less than 0.1 MPa.Spri-ngback phenomenon of the thin film is obvious,leading that force sensitivity stability of the thin films is bad, When loaded/unload with complex stress.And the force sensitive feature of the thin film is better under the condition of normal stress than that loaded/unloaded under the condition of comprehensive stress.