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.
出处
《复合材料学报》
EI
CAS
CSCD
北大核心
2005年第4期40-46,共7页
Acta Materiae Compositae Sinica
基金
广东省自然科学基金(021251)
教育部"留学回国人员启动基金"
广东省"千百十"优秀人才培养基金(Q02036)
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
carbon fiber-reinforced cement-matrix composite
pressure sensitivity
moisture content
tunneling effect
capacitance effect
