Analysis of the detection of welded joints

The article presents the possibilities of defects detection in the form of welds of leading steel elements, using the fiber Bragg gratings (FBG). Measurement of sensitivity to force change is ensured by shifting the FBG spectrum. Two steel samples of the same dimensions were used for the tests. The first one lacking significant defects in its structure, while the second one has been cut in the middle and it has been welded. FBG has been glued to the sample over its entire length. The results of measurements in the form of basic characteristics of the described stress sensor are presented below.