This paper describes quantitative evaluation of the nugget size and shape of resistance spot welds on stainless steel using ultrasonic pulse-echo amplitude. Here an empirical formula has been derived for predicting spot weld nugget diameter for sample having different thickness. The reliability as well as the accuracy of the empirical equation has been verified by comparing the calculated results based on ultrasonic response with the results obtained by X-ray (Radiography) and destructive testing.
Safi, A. M., Salam Akanda, M. A., Sadique, J., & Alam, M. S. (2014). Nondestructive evaluation of spot weld in stainless steel using ultrasonic immersion method. In Procedia Engineering (Vol. 90, pp. 110–115). Elsevier Ltd. https://doi.org/10.1016/j.proeng.2014.11.822