Acoustic Lens
Multylens system
Schematic view of the multilens US transducer for resistance spot weld inspection
Increasing of the resolution
Laser welding scans
20x20 mm subsurface acoustic image of laser spot weld
Impact Area in 12’ Pet Body Component
Array Transducer
Industrial Prototype for Spot Weld Monitoring
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Nonlinear methods
Some special cases of defects, invisible by usual acoustic
Thin cracks or other discontinuity
Glue layers
Small-grain structure (grain dimension less then wavelength)
Inclusions of materials with similar acoustical parameters
Images in Second Harmonic,
Reflection Mode Acoustic Microscope and
Receiving of double frequency
Non-Linear Ultrasound for NDE Inspection of Thin Layers
Near-Weld Region
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Click on image to enlarge
Experimental Observations
Samples: two steel 2-mm sheets, joined by resistive weld and polish to exclude surface effects
In-Process Spot Weld Monitoring
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