DIGITAL-COMPUTER ALGORITHMS TO CALCULATE ULTRASONIC WAVE SPEED

Ultrasonic wave speed measurements are required in many applications, including material property determination, microstructural characteriz ation, and flaw detection of materials. The accuracy and repeatability of results are dependent on both the hardware used to propagate and r eceive the ultrasonic waveforms and on the analysis for calculating wa ve speed. In this study, a comparison is made between five analysis al gorithms for calculating ultrasonic wave speed. The overlap, Hilbert t ransform, phase slope, cross correlation, and cepstrum algorithms are implemented using a commercial software package. Average wave speed an d standard deviation are compared for ten materials. Each algorithm ha s calculated wave speed within 1 percent of the mean for all five algo rithms. The most consistent results have been provided by the overlap, cross-correlation, and cepstrum algorithms, which have produced resul ts within 0.2 percent of the mean for the three algorithms.