MATHEMATICAL MODELLING OF TECHNOLOGICAL PROCESSES AND SYSTEMS
The direct problem in ultrasonic testing (UT) is: “Evaluation of attenuation coefficient by means velocity of ultrasonic wave propagation, frequency and grain size in polycrystalline materials”. The inverse problem in UT is formulate as “Non-destructive evaluation of grain size by measurement of acoustical characteristics”. The values of acoustical characteristics (V V f ) L T L ; ;α ; are measured, according ASTM E 494:2015. In this article a equation for grain size (D) is derived.