Residual Stress Detection by Measurement of Efficiency of Electromagnetic Generation of Ultrasound
I think I should thank George Matzkanin for starting everyone thinking in terms of magnetic phenomena. Yesterday we heard three papers describing the performance of electromagnetic transducers on nonmagnetic materials. The question was asked at the close of one, "Do these transducers work on ferrous materials?" The answer that I will give you is, "Yes, they do, and furthermore, the efficiency of the operation is directly related to the stress within the material." The mechanism of this relationship is very similar to the mechanism of the stress dependence of the Barkhausen effect. However, the information gained is distinct and complimentary.