An independent component analysis based approach for frequency modulated thermal wave imaging for subsurface defect detection in steel sample

2019 ◽  
Vol 98 ◽  
pp. 45-54 ◽  
Author(s):  
Javed Ahmad ◽  
Aparna Akula ◽  
Ravibabu Mulaveesala ◽  
H.K Sardana
Keyword(s):  
Independent Component Analysis ◽  
Defect Detection ◽  
Thermal Wave ◽  
Component Analysis ◽  
Steel Sample ◽  
Independent Component ◽  
Subsurface Defect ◽  
Wave Imaging ◽  
Thermal Wave Imaging

Material characterisation by enhanced resolution in non-stationary thermal wave imaging

2021 ◽  
Vol 63 (12) ◽  
pp. 721-726
Author(s):  
G T Vesala ◽  
V S Ghali ◽  
S Subhani ◽  
Y Naga Prasanthi
Keyword(s):  
Defect Detection ◽  
Thermal Wave ◽  
Signal To Noise Ratio ◽  
Empirical Relationship ◽  
Depth Resolution ◽  
Steel Sample ◽  
Detection Depth ◽  
Wave Imaging ◽  
Domain Phase ◽  
Thermal Wave Imaging

In the recent past, quadratic frequency-modulated thermal wave imaging (QFMTWI) has been advanced with a chirp z-transform (CZT)-based processing approach to facilitate enhanced subsurface anomaly detection, depth quantification and material property estimation with enhanced depth resolution. In the present study, the applicability of CZT-based phase analysis for foreign object defect detection in a structural steel sample using QFMTWI is validated through finite element-based numerical modelling rather than experimental verification due to limited available resources. Furthermore, the enhanced defect detection capability of the CZT phase approach is qualitatively compared with the frequency- and time-domain phase approaches using the defect signal-to-noise ratio (SNR) as a quality metric. Also, an empirical relationship between the observed phases and the thermal reflection coefficient is obtained, which recommends the CZT phase as a prominent approach for foreign material defect detection.

Sign in / Sign up

Export Citation Format

Share Document