作　　者： ; ;

机构地区： 汕头大学工学院土木工程系

出　　处： 《复合材料学报》 2005年第4期40-46,共7页

摘　　要： 对碳纤维水泥基复合材料的压敏特性进行了实验研究。结果发现,在含水量不同的情况下,碳纤维水泥基复合材料分别具有正、负两种压敏特性。含水量较高时,碳纤维水泥基材料的电阻相对变化率随应力的增大而增大,随应力的减小而减小,表现出正压敏性。而含水量较低时,电阻相对变化率随应力的增大而单调减小,随应力的减小而单调增大,表现出负压敏性,进而提出了一种双效应机理,并对这一物理现象进行了合理解释。 The pressure sensitive behaviors of carbon fiber-reinforced cement-matrix composites with different moisture contents were studied. The results show that the relative change in resistance ΔR/Ro varies with the moisture content of the composites. With higher moisture content, the relative change in resistance ΔR/Ro increases with the increase of compressive stress, and decreases during unloading, demonstrating the positive pressure sensitivity.However, when the moisture content is reduced after specimens＇being oven-dried, the relative change in resistance ΔR/Ro decreases monotonically with the increase of compressive stress, and increases monotonically during unloading, showing the negative pressure sensitivity. The mechanism for these phenomena is discussed.

关 键 词： 碳纤维水泥基复合材料 压敏性 含水量 隧穿效应 电容效应

领　　域： [一般工业技术]