Measurement of material properties of composites under high temperature using fiber Bragg grating sensors

Composite materials are widely used for aircraft, satellites, and other structures due to their good mechanical and thermal characteristics such as high specific stiffness and strength, a low coefficient of thermal expansion, and good heat-resistance. However, for the use of composites under high temperature, their material properties must be measured and verified at high temperatures. In this study, the material properties of T700/Epoxy were measured through a tension test of composite specimens with an embedded fiber Bragg grating sensor in a thermal chamber at temperatures of room temperature, 100degreesC, 200degreesC, 300degreesC, and 400degreesC. The effects of an optical fiber on the material properties of the composites were investigated through a pre-test of embedding an optical fiber. Finally, the material properties of composites, parallel to and perpendicular to the reinforcing fiber, were successfully shown to vary according to increases in the temperature.