Fiber orientation assessment on surface and beneath surface of carbon fiber reinforced composites using active infrared thermography

Abstract

Fiber orientation in composite materials is an important feature since the material’s strength and stiffness are related to the fiber orientation. In this paper, non-destructive infrared thermography is used to assess fiber orientation of carbon/PEEK (<i>Polyether ether ketone</i>) laminates on the surface and subsurface of the material. Specifically, a noncontact laser lock-in thermography (LLT) technique is used for fiber orientation measurement in composite materials. LLT utilizes a modulated continuous wave (CW) laser as a heat source for lock-in thermography instead of commonly used flash and halogen lamps. Experimental results show that fiber orientation on the first (surface) and second layers of the laminate can be successfully measured using this technique.