石墨烯水泥基复合材料的电学性能

Electrical Properties of Graphene Cement Based Composites

为探究石墨烯水泥基复合材料的电学性能,通过四电极法测试了不同湿度、温度以及外荷载作用下复合材料的电阻率变化,考虑了石墨烯掺量对复合材料湿敏性、温敏性和压敏性的影响,并分析了其内在机理.结果表明:石墨烯水泥基复合材料的电阻率随着相对含水量的减少而逐渐增加,高掺量石墨烯可以降低复合材料的湿敏性;环境绝对温度的升高会导致石墨烯水泥基复合材料的电阻率呈现对数式下降,复合材料温敏性的临界石墨烯质量分数为0.8%;循环压缩荷载下,随着外荷载值的增加,石墨烯水泥基复合材料的电阻率下降,而外荷载值的降低会导致复合材料的电阻率上升;当石墨烯质量分数从0%增至0.8%时,复合材料的电阻变化率曲线离散性大幅降低、电阻变化率增大.

In order to investigate the electrical properties of graphene cement based composites,four-probe method was used to explore the influence of moisture,temperature and external cyclic loading on the electrical resistivity of cement based composites.Meanwhile,the effect of graphene content on moisture sensitive,thermal sensitive and pressure sensitive properties of composites was also studied.The results show that the electrical resistivity of graphene cement based composites increases with the increase of relative water content,and the reduction of resistivity sensitivity to water content was observed in high graphene content composites.The electrical resistivity of composites logarithmic decreases with the increase of absolute temperature,where 0.8%is the critical graphene content.Under external cyclic loading,the electrical resistivity of composites decreases with the increase of external load value,whereas it increases with the decrease of external load value.With the graphene content increase from 0%to 0.8%,the dispersion of resistance change rate curves reduced remarkably and the resistance change rate of composites increase.