Laser Scanning Thermal Probe: Anovel Approach to Non-destructive Evaluation

Structural defects such as cracks have recently been identifiable through a new nondestructive evaluation (NDE) technique know as sonic IR or thennosonics. However, these defects are depicted through thennal imagining system as localized "hoI spots" indicating a general location of a defect without an accurate portrayal of the dimensions or shape of the defect. This paper demonstrates a new technique called Laser SealUling Thennal Probe, LSTP, which utilizes thennography with the use of heat application in strategic locations to observe spatial heat flow patterns. The LSTP records heat propagation across a defect area previously identified through the thennosonic technique. Thermal gradients will occur as heat traverses the crack and provide information to characterize the crack such as its length and shape.