Abstract
This paper describes applications of fiber Bragg grating (FBG) sensors to cure monitoring of composites during autoclave molding. FBG sensors are embedded into unidirectional glass fiber reinforced plastics (GFRP) laminates for measuring internal strain. Off-axis strain measurements by FBG sensors with angles of 0,45 and 90 degrees against reinforcing direction were conducted during cure. In addition, FBG temperature sensors were developed for cure monitoring of FRP laminates. Finally, simultaneous monitoring of strain and temperature during cure was conducted by using embedded FBG strain and temperature sensors. From the results, it appeared that FBG sensors were useful for residual strain monitoring during cure. The experimental results of the simultaneous measurement showed that this system had a good performance of strain measurement under temperature-changeable conditions. Therefore, it can be concluded that embedded FBG sensors are useful for cure monitoring of FRP laminates during autoclave molding.
