Application of Ultrasonic Spectral Analysis for the Study of Steels

Ensuring high quality, specific structures, and defined mechanical properties of materials requires the widespread application of non-destructive methods for control and investigation of the structural elements of materials, in particular ultrasonic methods. The subject of this study is samples of low-carbon steel, in which equilibrium ferrite-pearlite structures with different grain sizes have been obtained through targeted heat treatments. Through quantitative metallographic analysis, the average grain size, the percentages of ferrite and pearlite, and the grain size distribution have been determined. The aim of this study is to investigate the structural elements of carbon steels using an ultrasonic method. Ultrasonic spectral analysis is employed, which is based on the changes in the frequency spectrum of ultrasonic waves after their interaction with the material. The way ultrasonic waves scatter and attenuate in a polycrystalline material provides information about the size, shape, and distribution of the structural elements that make up the material. This work analyzes the influence of grain size distribution and the quantitative assessment of different phases on the attenuation of ultrasonic wave