Crack Length Determination by Ultrasonic Methods
Accurate calculation of the stress intensity factor on a given component under load relies on an accurate size determination of the flaws present in the component. The challenge to the NDE community has been development of reliable techniques to provide that accurate size determination. Many research groups have investigated this problem using ultrasonic methods with summaries of their techniques and results provided by various authors [1–3]. In general, the techniques developed fall into three general categories; (1) determination of crack length from signal amplitude measurements, (2) determination of crack length from time-of-flight measurements, and (3) determination of crack length using diffracted waves. Sketches of representative techniques in each category are shown in Figure 1.
KeywordsFatigue Crack Stress Intensity Factor Crack Length Crack Front Crack Depth
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