ABSTRACT
The ultrasonic fatigue technique is an accelerated testing method with a frequency far beyond that of conventional fatigue experiments and applications. A problem is naturally posed: Is there an important frequency influence on the experimental results? If the frequency effect is too great, the usability of the test data might be in question. Fortunately, results in the literature and our own experience indicate that for ultrasonic fatigue tests under low displacement amplitude and small deformation conditions, the frequency effect is small in most cases. Quite a few similarities between ultrasonic and conventional fatigue data have already been noted in previous chapters. The frequency effects are discussed in this chapter in detail. We will show that the frequency effect is much more significant between 10Hz and 0.001Hz than between 10Hz and 20kHz.
