On the basis of an analytical model for calculating the attenuation coefficient, it has been revealed that, to quantitatively evaluate the metal granularity, the attenuation coefficient must be measured at three frequencies. An ultrasonic technique for evaluating the metal granularity of axles of wheel pairs taking into account the influence of the cylindrical injection and reflection surfaces and the roughness of the axle surfaces is proposed. The anisotropy coefficient of the metal of axles, Fa = 3.8 x 10-3, has been experimentally determined and the anisotropy coefficients of hypoeutectoid steels have been calculated as functions of the percent ratio of structural components. The obtained results can be used in estimating the metal granularity of axles at the manufacturing factories and during testing of the structure of axles in accordance with at the centers of formation of wheel pairs in the case of a decrease in the bottom echo signal below the rejection level. In addition, the proposed ultrasonic method and the obtained values of the anisotropy coefficients make it possible to quantitatively evaluate the metal granularity of objects made of hypoeutectoid steels with different contents of ferrite and pearlite structures.
An ultrasonic method for quantitative evaluation of the metal structure of axles of wheel pairs
Ein Ultraschallverfahren zur quantitativen Bewertung von Metallgefüge an Achsen und Radsätzen
Russian Journal of Nondestructive Testing ; 45 , 7 ; 464-471
2009
8 Seiten, 6 Bilder, 3 Tabellen, 18 Quellen
Aufsatz (Zeitschrift)
Englisch
Ultrasonic detection of cracks in wheel set axles
Tema Archiv | 1987
|Engineering Index Backfile | 1912
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