The application of carbon fiber resistancein monitoring of curing

Thermal residual stress in resin matrix composite due to the different coefficient of thermal expansion (CTE). The CTE of carbon fiber is lower than resin matrix. Based on mechanics, rising temperature will induce tensile stress, cooling down will induce compress in fiber. There exists expanding and shrinkage during curing process of epoxy. In single fiber composite system, they play different roles, present with tensile and compress stress on fiber. This paper deals with the relationship of the carbon fiber resistance with strain and temperature. The effect of expanding and shrinkage on residual stress is got by the fiber resistant measurement. Resistance variety curve of the experiment shows the chemical process during resin solidification. The shear stress between fiber and matrix existing during temperature load can also measured by the same method. The carbon fiber's resistant can be used as sensor to monitor and control the curing process. This is a simple and effective method to research the curing process.