Dresden 2006 – wissenschaftliches Programm

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MM: Metall- und Materialphysik

MM 8: Symposium Modern Metallic Materials Design II

MM 8.7: Vortrag

Montag, 27. März 2006, 16:15–16:30, IFW B

Analyse of frequency spectrum in the austenitic steel sample — •Remus Zagan, Petre Petculescu, and Niculae Peride — Ovidius University of Constanta, Mamaia Ave. 124, 900527, Constanta, Romania

This paper presents some experimental results in order to evaluate the effect of wavelet transform (WT) filtering on ultrasonic spectral analysis. By applying WT, the authors proved that it is possible to compress and filter the ultrasonic signal buried in noise, without any loss of accuracy in the time measurement. The experiments were made on an austenitic stainless steel sample 16Mo3. For the peak frequency the following values were found: 4.11 MHz by power spectrum (PS) and 4.111 MHz by power spectrum density (PSD). In this paper, we have used the power spectrum (PS) and power spectral density (PSD) for the determination of the frequency values of the spectrum and spectrum resonance spacing domains (SRSD). The experimental results presented here were obtained by the direct contact method using silicon gel as the coupling medium by pulse-echo technique. The instrumentation consisted of an IPR-100 pulser-receiver, a A/D-90 converter and a SMC-4 from Physical Acoustic Corporation, a sampler and a spectral analyzer. Keywords: ultrasounds, wavelets, power spectrum,power spectral density.