Finite-element modeling of sonic IR imaging of cracks in aluminum and titanium alloys

In previous conferences, we have described Sonic infrared (IR) Imaging, and presented both experimental and theoretical work using induced chaotic sound within aircraft parts and structures. We have demonstrated that induced chaotic sound is much more effective in producing heat in defects than is single-frequency sound, thus resulting in stronger IR signals. Therefore, for the same defect, the probability of detection with chaotic sound is much higher than with non-chaotic sound. In this paper, we present a finite-element study of the vibration and heating in aluminum and titanium to investigate the effects of their different material properties. We allow both friction and plastic deformation as sources of heating in our models.