炭黑/硅橡胶导电复合材料力敏元件温度响应试验研究

利用炭黑/硅橡胶导电复合材料制作了大变形力敏传感元件,对其温度荷载下的电阻响应进行了试验研究,并根据其导电机理对温敏特性进行了深入分析.试验发现制作的大变形力敏传感元件具有正温度系数特性,电阻随温度的升高而增大;温度稳定时,具有电阻弛豫现象.硅橡胶基体随温度变化体积发生变化是造成复合材料温度敏感性的主要原因;同时,温度变化也会影响电子跃迁能力,进而影响到复合材料温度响应.橡胶基体的粘弹性以及试样具有一定厚度的尺寸效应是导致其温度响应滞后性的主要原因.

Temperature Response Test of Carbon Black/Conductive Silicon Rubber Composite Force-Sensitive Sensor

The large deformation force-sensitive sensing element was developed by carbon black/silicone rubber con-ductive composites. The temperature sensitivity of the composite was studied by temperature test,and the tempera-ture sensitive characteristics were analyzed according to its electric conduction mechanism. It was found that the car-bon black/silicone rubber conductive composite material exhibits a positive temperature coefficient characteristic and the resistance was increased with the increase of temperature. The resistance relaxation phenomenon was found when the temperature was stable. The change of the volume of silicone rubber matrix with temperature is the main reason causing the temperature sensitivity. At the same time,the temperature change will also affect the ability of electronic transitions,thereby affecting the temperature response of the composites. The viscoelastic of rubber matrix and the size effect of the sample which has a certain thickness are the main reason for the temperature response lag.