碳纳米管/水泥基复合材料导电性与力敏特性研究  

Study on the Electrical Conductivity and Pressure Sensitive of Carbon Nanotubes / Cement- based Composite Materials

作　　者：刘小艳[1] 刘岩[1] 明维[1] 左俊卿[1] 

机构地区：[1]河海大学力学与材料学院,江苏南京210098

出　　处：《粉煤灰综合利用》2015年第2期6-9,共4页Fly Ash Comprehensive Utilization

基　　金：国家自然科学基金(51009057)

摘　　要：为改善水泥基复合材料的导电性,通过添加一定掺量的碳纳米管,制备了碳纳米管/水泥基复合材料。采用四电极伏安法和扫描电子显微镜的测试方法研究了碳纳米管的掺量对碳纳米管/水泥基复合材料的导电性和力敏特性的影响。试验结果表明,0.05%-0.5%的碳纳米管掺量处于渗流区内,此时试件的电阻率随碳纳米管掺量的增加而降低;在循环轴压应力作用下,试件的电阻率随应力的增大而减小,随应力的减小而增大,且变化曲线呈可回复近似单调的变化规律,同时试件的电阻相对变化率以及力敏灵敏度随碳纳米管掺量的增加而增大,显示出良好的力敏特性。这表明碳纳米管/水泥基复合材料的导电性与其受载过程有着密切的关联性,从而有望用于混凝土内部应力及损伤的监测。The certain proportion of carbon nanotubes were added into the cement- based composite materials to improve the electrical conductivity. The effect of the content of carbon nanotubes on the conductivity and characteristic of pressure sensitivity of the composite materials was investigated by four electrodes voltammetry and scanning electron microscopy. The results show that the content of carbon nanotube used for the study is in the scope of the percolation threshold,and the resistivity of the specimens decreases with increasing the content of carbon nanotubes.The results also indicate that the composite materials have the characteristic of the pressure sensitive. On one hand,the resistivity of the specimens decreases with the increase of pressure,and increases with the decrease of the pressure,which also shows the linearly reversible changing curves.On the other hand,the relative change rate of the resistance and the sensitivity of the perssure sensitive increases with increasing the content of carbon nanotubes under uniaxial cyclic compressive stress. It indicates that it has close correlation between the conductivity of carbon nanotubes /cement- based composite materials and its loading process,which is expected to monitor the internal stress and damage of concrete.

关 键 词：碳纳米管 水泥基材料 电阻率 力敏特性 

分 类 号：TU431[建筑科学—岩土工程]