In-situ real-time imaging of subsurface damage evolution in carbon fiber composites with shearography

Carbon fiber composites are complex material systems comprising components of different length scales. It is important to understand the interactions of these components and their influence on the overall mechanical properties of the composites for development of new or improved composite materials. However, it is challenging to experimentally image the damage evolution in composites with existing tools. In this paper, we apply shearography technique for real-time in-situ imaging of subsurface damage evolution in carbon fiber composites during open-hole tensile (OHT) tests. Due to its high sensitivity to out-of-plane displacement derivative, shearography can record the initiation and growth of subsurface defects in real-time. Comparison with digital image correlation shows that shearography can provide better defect imaging results. The shearography technique provides a convenient and high-sensitive solution to visualize damage evolution in carbon fiber composites during mechanical tests.