Abstract
In this research, optical fiber sensors and shape memory alloys (SMA) were incorporated into sandwich panels for development of a smart honeycomb structure with damage detection and shape recovery functions. First, small-diameter fiber Bragg grating (FBG) sensors were embedded in the adhesive layer between a CFRP facesheet and an aluminum honeycomb core. From the change in the reflection spectrum of the FBG sensors, the debonding between the facesheet and the core and the deformation of the facesheet due to impact loading could be well detected. Then, the authors developed the SMA honeycomb core and bonded the CFRP facesheets to the core. When an impact load was applied to the panel, the cell walls of the core were buckled and the facesheet was bent. However, after the panel was heated over the reverse transformation temperature of the SMA, the core buckling disappeared and the deflection of the facesheet was relieved. Hence the bending stiffness of the panel could be recovered.
