TY - JOUR
T1 - Enhanced ultrasonic detection of near-surface flaws using transverse-wave backscatter
AU - Huang, Yuantian
AU - Turner, Joseph A.
AU - Song, Yongfeng
AU - Ni, Peijun
AU - Li, Xiongbing
N1 - Funding Information:
This work was supported by the National Natural Science Foundation of China [grant numbers 51575541, 51711530231], and the Fundamental Research Funds for the Central Universities of Central South University [grant numbers 2019zzts538]. The authors would like to thank Drs. Ping Hu and Andrea Arguelles for valuable discussions.
Funding Information:
This work was supported by the National Natural Science Foundation of China [grant numbers 51575541 , 51711530231 ], and the Fundamental Research Funds for the Central Universities of Central South University [grant numbers 2019zzts538 ]. The authors would like to thank Drs. Ping Hu and Andrea Arguelles for valuable discussions.
Publisher Copyright:
© 2019 Elsevier B.V.
PY - 2019/9
Y1 - 2019/9
N2 - Diffuse ultrasonic backscatter measurements have been shown to enhance the detection capability of sub-wavelength flaws when combined with extreme value statistics. However, for a normal-incidence immersion measurement, a “dead zone” created by the ring-down of the front-wall echo will hide near-surface flaws. In this article, a pulse-echo transverse wave backscatter measurement is used to detect near-surface flaws under high gain. The approach is validated using a magnesium specimen with side-drilled holes. The confidence bounds of the grain noise from this specimen are given by a transverse-to-transverse scattering model, which takes the grain size distribution and the hexagonal crystal symmetry into account. The upper bound is then treated as a time-dependent threshold for the C-scan. Experiments show that the developed method has good performance for detecting sub-wavelength, near-surface flaws, and can suppress both missed detections and false positives.
AB - Diffuse ultrasonic backscatter measurements have been shown to enhance the detection capability of sub-wavelength flaws when combined with extreme value statistics. However, for a normal-incidence immersion measurement, a “dead zone” created by the ring-down of the front-wall echo will hide near-surface flaws. In this article, a pulse-echo transverse wave backscatter measurement is used to detect near-surface flaws under high gain. The approach is validated using a magnesium specimen with side-drilled holes. The confidence bounds of the grain noise from this specimen are given by a transverse-to-transverse scattering model, which takes the grain size distribution and the hexagonal crystal symmetry into account. The upper bound is then treated as a time-dependent threshold for the C-scan. Experiments show that the developed method has good performance for detecting sub-wavelength, near-surface flaws, and can suppress both missed detections and false positives.
KW - Extreme value statistics
KW - Grain size distribution
KW - Sub-wavelength near-surface flaws
KW - Time-dependent threshold
KW - Transverse-to-transverse (T-T) scattering
KW - Ultrasonic testing
UR - http://www.scopus.com/inward/record.url?scp=85066440228&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85066440228&partnerID=8YFLogxK
U2 - 10.1016/j.ultras.2019.05.010
DO - 10.1016/j.ultras.2019.05.010
M3 - Article
C2 - 31170544
AN - SCOPUS:85066440228
SN - 0041-624X
VL - 98
SP - 20
EP - 27
JO - Ultrasonics
JF - Ultrasonics
ER -