TY - GEN
T1 - Artificial disbonds for calibration of transient thermography inspection of thermal barrier coating systems
AU - Ptaszek, G.
AU - Cawley, P.
AU - Almond, D.
AU - Pickering, S.
PY - 2011/1/1
Y1 - 2011/1/1
N2 - Transient thermography is commonly used for the detection of disbonds in thermal barrier coatings (TBC). As for other NDT techniques, reference test specimens are required for calibration, but unfortunately, real disbonds are very difficult to use because it is difficult to control their size, and larger ones tend to spall. Flat bottomed holes are commonly used, but these over-estimate the thermal contrast obtained for a defect of a given diameter. This paper quantifies the differences in thermal response using finite element analysis validated by experiments, and proposes a form of artificial disbond that gives a better representation of the thermal responses seen with real defects. Real disbonds tend to have a non-uniform gap between the disbonded surfaces across the defect, and the effect of this on the thermal response is evaluated using finite element simulations. It is shown that the effect can be compensated for by adjusting the diameter of the calibration defect compared to the real defect.
AB - Transient thermography is commonly used for the detection of disbonds in thermal barrier coatings (TBC). As for other NDT techniques, reference test specimens are required for calibration, but unfortunately, real disbonds are very difficult to use because it is difficult to control their size, and larger ones tend to spall. Flat bottomed holes are commonly used, but these over-estimate the thermal contrast obtained for a defect of a given diameter. This paper quantifies the differences in thermal response using finite element analysis validated by experiments, and proposes a form of artificial disbond that gives a better representation of the thermal responses seen with real defects. Real disbonds tend to have a non-uniform gap between the disbonded surfaces across the defect, and the effect of this on the thermal response is evaluated using finite element simulations. It is shown that the effect can be compensated for by adjusting the diameter of the calibration defect compared to the real defect.
UR - http://www.scopus.com/inward/record.url?scp=84906219984&partnerID=8YFLogxK
M3 - Chapter in a published conference proceeding
AN - SCOPUS:84906219984
SN - 9781618393432
T3 - 50th Annual Conference of the British Institute of Non-Destructive Testing 2011, NDT 2011 Held in conjunction with the Materials Testing Exhibition, MT 2011
BT - 50th Annual Conference of the British Institute of Non-Destructive Testing 2011, NDT 2011 Held in conjunction with the Materials Testing Exhibition, MT 2011
PB - British Institute of Non-Destructive Testing
T2 - 50th Annual Conference of the British Institute of Non-Destructive Testing 2011, BINDT 2011
Y2 - 13 September 2011 through 15 September 2011
ER -