To ensure integrity of the structure such as nuclear power plant, the demand has been increased for establishing nondestructive method for detection of pre-existing plastic st rain. In this study, potentiostatic etching method is applied to detect and measure plastic strain imposed to austenitic stainless steel by tensile straining. After potensiost atic etching (1N HNO3, -600mVsce, 20min), the twin band appears as etched line on the surface of specimens. The etched twin band is observed by optical microsc...
英字タイトル:
Potentiostatic Etching Method for Detection of Pre-existing Plastic Strainin Austenitic Stainless Steel

A composite-type optical fiberscope was combined with a laser processing head to repair heat exchange pipes of Fast Breeder Reactor (FBR). The head can rotate axially and move back and forth longitudinally in the 1-inch pipes. The property of fiberscope and the motion of the head can successfully observe the pipe’s inner surface to find the cracks which should be repaired by laser welding. The project, which aims for developing the integrated system of inspection and repair, proposes an effective cost...
英字タイトル:
Development of a Laser Processing Head Using a Composite-type Optical Fiberscope to Inspect and Repair 1-inch Heat Exchanger Pipes