中文摘要：

碳纤维是一种十分重要的新型材料，是先进复合材料中最重要的增强材料之一，同时又是一种功能材料。研究了连续碳纤维单丝的应变电阻效应，分析了在拉应力作用下其电阻率的变化规律。结果表明：连续碳纤维单丝的电阻应变灵敏系数为1．38，比常用电阻应变片的要低，原因是碳纤维的电阻率在拉应力作用下是减小的。另外连续碳纤维受拉时，其电阻的变化由纤维几何尺寸及电阻率的变化引起，但主要是由几何尺寸的变化而引起的。同时，测试了连续碳纤维单丝的力学性能。

英文摘要：

Carbon fibers, a new kind of very important material, are not only one of the most important reinforcing materials in advanced composite material, but also functional materials. The effect of tensile strain on electrical resistance of continuous carbon fiber monofilament was investigated in this paper. Results show that the resistance of carbon fiber increases during the tensile test, the gauge factor （fractional change in resistance per unit strain） of continuous carbon fiber monofilament is 1.38, which is lower than that of the commonly-used resistance strain gauge. The reason is that the electrical resistivity of carbon fiber decreases under tension. As the carbon fiber is stretched, the change of the resistance depends on the change of both the geometry of fiber and the resistivity. However, the former influence is the main. In the meantime, the mechanical properties of carbon fiber monofilament were reported in this paper.