After cure: UT, CT, shearography
In-process inspection watches each ply; after cure, the question is whether the finished part is sound inside. Visual inspection covers the surface. Ultrasound finds and sizes voids, disbonds and delaminations by timing echoes.
Predict · at 1:16 in the video
A five-millimetre laminate. The back-wall echo arrives at three point three microseconds, the flaw echo at one point three. How deep is the flaw?
About two millimetres. The sound travels at the same speed to both, so depth is just a ratio: one point three over three point three, times five. That also tells you the speed: about three thousand metres a second, typical for carbon fibre and epoxy through the thickness.
Automated Fiber Placement: Status, Challenges, and Evolution, Ramy Harik & Alex Brasington.
- Chapter 6, section 5.A
- Chapter 6, section 5.B
- Chapter 6, section 5.C
Simulations in this lesson are our own. Where the numbers are invented to show a mechanism, the video says so on screen.
