Numerical Simulation on Thermal Response for Dynamic Non-Destructive Detection of Weak Bonds in Carbon Fiber Reinforced Polymer

The aim of this work is to study the pulse thermal response on the nondestructive inspection of weak bond in carbon fiber reinforced polymer (CFRP) using finite element (FE) model. Simulations of thermal responses of weak bonds to external loads have been conducted using finite element models of the CFRP specimens with defects/weak bonds sandwiched in between CFRP layers. The resulting thermal evolution field is comprised of thermal properties variation between the defect and CFRP; and the important characteristic of the defects can be obtained from evolution of the field distribution. We study the depth and size of defect buried in various layers; and the result shows promising defect detection with resolution contrast up to ∼ 0.07K. Also, we estimate the thermal contrast when the thickness of defect is approximately to zero for predicting the zero-thickness weak bonds in the laminate layers.