The next generation of aircraft could be thinner and lighter thanks to the development of a nonlinear acoustic imaging technique that can detect damage previously invisible to acoustic imaging systems. According to Dr. Jack Potter, research assistant in the department of mechanical engineering at the University of Bristol’s Ultrasonics and Non-destructive Testing research group, it has long been understood that acoustic nonlinearity is sensitive to many physical properties including material microstructure and mechanical damage.
“Imaging acoustic nonlinearity not only provides sensitivity to smaller defects than is currently possible, but may have the potential to detect damage before macroscopic material changes occur,” he said. “This would enable intervention before cracks have even begun to form as well as predicting the remaining life of an engineering structure. Crucially, the technique has been achieved using standard inspection equipment, which will allow for the rapid implementation of the technique in numerous applications.”
Currently engineers are able to produce images of the interior of components using ultrasound but can detect only large problems such as cracks. “It’s like being able to detect only broken bones in a medical environment,” he said.
