The body panels are triple stamped, says Bedrosian, "to give greater definition of the character lines and impact greater strength," and the limited-availability Super Silver paint job is hand-polished using both medium and fine-grit abrasives and finished with three clear coats In additional, each body is placed on a shaker table where technicians, says Bedrosian, "are using the results to improve the weld nugget size
and spacing based on its effect on the torsional and bending response of the structure.
A logic conclusion could be that the nugget size has reached its maximum which is limited over the diameter of the electrodes.
Table 1 shows the average values of the nugget size at several phase fires and associated with it the corresponding currents, strokes and forces.
As can be seen in Table 1 and already concluded the nugget size is converging to a definite value (the electrode diameter).
Nugget size at different currents Phase Fire [%] 59 64 69 74 79 Current [kA] 3,13 3,23 3,40 3,51 3,61 Stroke [[micro]m] 129 147 165 188 204 Force [N] 15,9 17,4 18,9 22,1 24,1 Nugget [empty set] [mm] d.
Even attempting to estimate nugget size based on the amplitude of the received signal, the detailed information about the nugget is limited.
Correlation of measurements with peel tests is very important, since most industrial standards are based on the nugget size measured after the peel test.
These coupons simulate spot welds with nugget sizes ranging from 2.
For optimum weld penetration without voids, the system must control the 3/8" nugget size
within a narrow window, thus weld specs are critical.
Non-Contact Measurement of Nugget Size
of Spot Welding Using Focused Air-Coupled Ultrasound
Detailed pitting in the central part of the structure revealed the presence of fresh and angular gold indicating a nearby source with grains of gold ranging from fine to nugget size