TY - JOUR
T1 - Effect of adhesion force between crack planes on subharmonic and DC responses in nonlinear ultrasound
AU - Ohara, Yoshikazu
AU - Mihara, Tsuyoshi
AU - Yamanaka, Kazushi
N1 - Funding Information:
This work was supported by a Grant-in-Aid for Scientific Research (Nos. 15360377, 15656179 and 16206071) from the Ministry of Education, Culture, Sports, Science and Technology.
PY - 2006/2
Y1 - 2006/2
N2 - Subharmonic and DC responses in nonlinear ultrasound have been expected as a possible means of detecting closed cracks. Recently, it has been reported that subharmonics in a closed crack markedly increases above a certain input wave amplitude. Such a phenomenon is called "threshold behavior". However, the mechanism of threshold behavior has yet to be elucidated. To clarify this, we introduced adhesion force as a short-range force into the previous analytical model, which expresses the nonlinear contact vibrations of crack planes with intense ultrasound and provides a DC displacement as an approximation of the subharmonic response. Consequently, upward convex curves of displacement against input wave amplitude above the threshold were reproduced for the first time. The validity of the derived analytical solution is discussed by comparison with experimentally observed subharmonics.
AB - Subharmonic and DC responses in nonlinear ultrasound have been expected as a possible means of detecting closed cracks. Recently, it has been reported that subharmonics in a closed crack markedly increases above a certain input wave amplitude. Such a phenomenon is called "threshold behavior". However, the mechanism of threshold behavior has yet to be elucidated. To clarify this, we introduced adhesion force as a short-range force into the previous analytical model, which expresses the nonlinear contact vibrations of crack planes with intense ultrasound and provides a DC displacement as an approximation of the subharmonic response. Consequently, upward convex curves of displacement against input wave amplitude above the threshold were reproduced for the first time. The validity of the derived analytical solution is discussed by comparison with experimentally observed subharmonics.
KW - Adhesion force
KW - Closed cracks
KW - Nonlinear ultrasound
KW - Threshold behavior of subharmonics
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U2 - 10.1016/j.ultras.2005.10.006
DO - 10.1016/j.ultras.2005.10.006
M3 - Article
C2 - 16376399
AN - SCOPUS:32044440253
VL - 44
SP - 194
EP - 199
JO - Ultrasonics
JF - Ultrasonics
SN - 0041-624X
IS - 2
ER -