Abstract:

In order to embed carbon nanotube yarn sensor into composite material. Intelligent 3-D braided composites using 3-D braided technology was constructed. According to the braiding structure of three-dimensional six-direction braided composites, the mathematic model of carriers movement of braiding machine was constructed. The method of calculating the number and length of embedded carbon nanotube yarns with intelligent composites proposed. The characteristics of resistance changing for carbon nanotube yarns under the loading were analyzed. Experiments show that the error of the length and actual length of the carbon nanotube yarn calculated by the Bezier-curve is less than 1%. When the tensile strain exceeds 2%, the strain of the embedded carbon nanotube yarns begin to appear nonlinear. The loading and unloading of the specimen has some influence on the resistance dhange of the carbon nanotube yarn. After the load is unloaded, the carbon nanotube yarn will produce the residual resistance.

Key words: intelligent three-dimensional composite, carbon nanotube yarn, matrix theory, Bexier curve, sensor strain coefficient