Relation between defect depth and standard thermal contrast on the steel surface in pulsed thermography
نویسنده
چکیده
The work is devoted to experimental determination of the diameter and the depth of simulated subsurface defects in steel using pulse thermography (PT). The simulated defects had a form of flat-bottom holes of diameter 1.0-5.0 mm and depth 0.3–1.5 mm. The defect diameter has been reconstructed on the basic of analysis of the rate of temperature decrease on the surface of tested specimen after its heating by the heat pulse. Defect depth has been estimated from the dependence of thermal contrast on the tested surface vs. self-cooling time. Experimental results are presented.
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