Nondestructive characterization of transparent laminate systems subject to low velocity impacts

Multi-layer, multi-material transparent laminate systems are used to enhance protection efficiency for ground vehicle windshield and window applications while ensuring sufficient visibility for the operator. Impact damage caused by low velocity strikes may result in crack formation in the transparent materials or delaminations between layers, which can impair visibility and affect performance. In this effort, transparent laminate systems have been nondestructively evaluated in a pre-impact, baseline state using visual inspection, cross-polarization imaging, and ultrasound characterization. After subjecting the laminate systems to a series of low velocity impact tests, the same nondestructive methods were used for characterization of the post-impact state. The effects of cumulative damage to the laminate systems were also studied by impacting them multiple times at the same location and observing the increase in damage and resulting damage mechanisms. This work provided a means for comparison of transparen...