基于炭黑填充导电橡胶的力敏传感器的灵敏度

以通用有效介质理论为基础, 给出了炭黑填充导电橡胶(炭黑/橡胶)的力敏传感器灵敏度计算方程。采用该方程并结合形变和压阻效应, 分析了影响力敏导电炭黑/橡胶的灵敏度的主要参数。结果表明: 炭黑体积分数是影响力敏导电炭黑/橡胶的灵敏度的主要参数。当炭黑体积分数在临界体积分数附近时, 力敏导电炭黑/橡胶的灵敏度为0.1～11.5 MPa^-1, 其敏感机制主要为压阻效应。当炭黑体积分数在渗流区时, 灵敏度为0.2～3.6 MPa^-1, 其敏感机制还与接触压力的大小有关, 压力较小时, 主要为压阻效应; 压力较大时, 主要为应变效应。若炭黑体积分数在传导区, 灵敏度为0.3～1.7 MPa^-1, 其敏感机制主要为应变效应。

Mechanical sensitivity of pressure-sensitive sensor based on conductive rubber filled by carbon black

An equation of mechanical sensitivity of pressure-sensitive sensor based on conductive rubber filled by carbon black (CB) was given by general effective media theory. According the equation, mechanical sensitivity was studied by the strain effect, the piezoresistive effect and major parameters of the composite. It concludes that the volume fraction of CB has a great impact on mechanical sensitivity. When the volume fraction of CB is close to the critical volume fraction, the scope of sensitivity is 0.1-11.5 MPa^-1, and the piezoresistive effect is the main sensitive mechanism. When the volume fraction of CB is within the percolation zone, the scope of sensitivity is 0.2-3.6 MPa^-1 , and sensitive mechanism is related to the pressure, i. e. when the pressure is kept at a low value, the piezoresistive effect plays a main role, whereas the pressure is kept at a high value, the strain effect would play a main role. When the volume fraction of CB is within the conductive zone, the scope of sensitivity is 0.3-1.7 MPa^-1, and the strain effect is the main sensitive mechanism.