以三元嵌段共聚硅橡胶为基体,Fe73.5Cu1Nb3Si13.5B9软磁粉为应力敏感填充粒子,采用机械共混和精密铸压热成型方法制备出系列粉体含量的Fe73.5Cu1Nb3Si13.5B9软磁粉/硅橡胶接触应力敏感复合材料,重点研究了其交流阻抗、直流电阻、粒子间及粒子与硅橡胶间相互作用程度等性能的逾渗特性。研究表明,该柔性力敏复合材料具有较显著的交流阻抗双逾渗特性。分析发现,“第一逾渗区”内材料的交流阻抗值由粒子的隧道跃迁主导,“第二逾渗区”内材料的交流阻抗大小取决于Fe73.5Cu1Nb3Si13.5B9粒子链间的接触电阻值。
Fe73.5 Cul Nb3 Si13.5 B9 soft magnetic powder/silicone rubber composites with different powder contents are prepared by mechanical blending and precise cast pressure hot forming method, using ternary block copolymerization silicone rubber as the matrices and Fe13.5 CulNb3Si13. 5 B9 soft magnetic powder as functional filler particles. The percolation characters of the composite are deeply studied through alternating current impedance, direct current resistance and the interaction degree of particles and particle with silicone rubber. It is shown that the flexible stress sensitive composite presents remarkable double percolation character of alternating-current impedance and it is also found that the alternating current impedance in "the first percolation area" is caused by the particle tunnel transition and "the second percolation area" depends on the contact resistance of Fe73.5 Cul Nb3 Si13.5 B9 particle chains.