Nondestructive Image Evaluation of Welded Zone of Steel Plate using Photoacoustic Microscope

Abstract

The nondestructive evaluation (NDE) of welded steel plates was performed using photoacoustic microscope (PAM). Specimens were prepared by changing the maximum welding current to 5, 6.5, and 8 kA. A noncontact inspection without having to assemble a transducer was performed, and the results were compared with those of destructive inspection using an optical microscope. The agreement of NDE using a PAM and results from an actual shear fracture destructive test was good. The large fluctuation in the PA signal measured for the steel plates welded at the small current suggests the inhomogeneity of the inside welded region. Furthermore, visualization of the welded region suggests the feasibility of obtaining information on the status or uniformity of the inner welded region, which is difficult to measure by the other methods.

Visualization of Mode Conversion of Lamb-Type Waves in Glass Plates Using Pulsed Light Source

“…[1][2][3][4][5][6] Above all, methods of visualization in real time are demanded. Results of these visualization contribute to nondestructive tests [7][8][9][10][11] and medical fields 12,13) as shown in the acoustical focusing lens, among others.…”

Photoacoustic Imaging with a Line-Focus Laser Beam for Rapid Inspection and Tomographic Characterization of Simulated Surface and Undersurface Defects

“…The photoacoustic microscope (PAM) is a useful tool for non-destructive imaging [1][2][3] and quantitative measurements [4] of surface defects in solid specimens. Previously, the use of a line-focus laser beam for inspecting welded metal plates by photoacoustic (PA) imaging was proposed [5].…”

Ultraviolet Excitation Photothermal Spectroscopy of Non-Labeled Amino Acids and Visible Light-Induced Signal Enhancement

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