TY - JOUR
T1 - Nondestructive Characterization of Bifurcated Crack by Potential Drop Technique
AU - Saka, M.
AU - Yuasa, D.
AU - Abé, H.
AU - Sugino, K.
N1 - Funding Information:
This work was partIy supported by The Ministry of Education, Science and Culture under Grant-in-Aid for Developmental Scientific Research (B) 02555021.
PY - 1992/6/1
Y1 - 1992/6/1
N2 - A method was presented for the nondestructive evaluation of a crack bifurcated from a horizontal crack in a rail. The method was based on the measurement of the difference and distribution of d.c. electrical potential on the top surface of the rail. First, a problem of current flow in a plate, which contained horizontal and bifurcated cracks and was subjected to a uniform current, was analyzed numerically by using a 2-D finite element method. The potential distribution on the measuring surface of the plate was obtained for various combinations of the cracks. The potential distribution showed a remarkable change in its slope just above both ends of the horizontal crack. Also the relation between the vertical component of the bifurcated crack and the total potential difference above the horizontal crack was revealed to be independent of the combinations of the cracks. Next, in order to characterize the cracks in actual rail based on the 2-D numerical analysis, a method was introduced for obtaining a rectangular section electrically equivalent to the section of actual rail. Finally, it was verified by experiments using rail specimens that the cracks were characterized quantitatively through the present numerical results together with the use of the equivalent section.
AB - A method was presented for the nondestructive evaluation of a crack bifurcated from a horizontal crack in a rail. The method was based on the measurement of the difference and distribution of d.c. electrical potential on the top surface of the rail. First, a problem of current flow in a plate, which contained horizontal and bifurcated cracks and was subjected to a uniform current, was analyzed numerically by using a 2-D finite element method. The potential distribution on the measuring surface of the plate was obtained for various combinations of the cracks. The potential distribution showed a remarkable change in its slope just above both ends of the horizontal crack. Also the relation between the vertical component of the bifurcated crack and the total potential difference above the horizontal crack was revealed to be independent of the combinations of the cracks. Next, in order to characterize the cracks in actual rail based on the 2-D numerical analysis, a method was introduced for obtaining a rectangular section electrically equivalent to the section of actual rail. Finally, it was verified by experiments using rail specimens that the cracks were characterized quantitatively through the present numerical results together with the use of the equivalent section.
KW - Bifurcated crack
KW - Finite element method
KW - Potential drop technique
KW - Rail
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U2 - 10.1080/10589759208952988
DO - 10.1080/10589759208952988
M3 - Article
AN - SCOPUS:0027073010
VL - 7
SP - 61
EP - 72
JO - Nondestructive Testing and Evaluation
JF - Nondestructive Testing and Evaluation
SN - 1058-9759
IS - 1-6
ER -