Ultrasonic Non-Destructive Testing (NDT) is becoming popular with automotive manufacturers to verify the integrity of a resistance spot weld of advanced high strength steels. Systems have advanced algorithms to calculate and display the A-Scan and C-Scan images and results from a test scan of a spot weld. The more that can be done in hardware versus software means that fewer calculations are needed to be done by the simulation software, which can provide more accurate results more quickly.
One of the key things that must be accounted for is the concave surface of a resistance spot weld. EWI scientists researched this and used computational modeling and simulations to develop a reliable, high-frequency 3-D matrix phased array (MPA) spherical shaped probe with an appropriate delay line and an optimal propagation distance for the ultrasonic beam to be focused on a spot weld. A commercially available CIVA modeling package was used to perform modeling and simulation to design the optimum probe configuration and dimensions.
The resulting spherical shaped Matrix Phased Array probe provides quicker, more accurate results that operators can rely on to analyze whether a spot weld meets the minimum requirements and provide them with a PASS/FAIL analysis.
This technology can be seen in the system that was developed in partnership with Progenero Products to create the SpotSight system.