Shadow Formation
Shadowing is a geometric effect in radiographic testing where uneven part thickness leads to varying gray values on the detector. This requires exact alignment of the radiation source to the flaw geometry.
Physicochemical mechanism of action
Radiographic testing uses X-rays or gamma rays that pass through the material and are imaged on a detector. When component thickness is uneven, the radiation is absorbed differently at different points. This leads to varying gray values on the detector screen, which appear as shadow patterns.
Metallurgical relevance & risks in welding
Shadow patterns can provide important information about component defects or irregularities. If not interpreted correctly or if the radiation source is not precisely aligned, this can lead to detection errors. This can result in inaccurate test results and possible safety risks in structures or machines.
Workshop practice & instructions
To correctly recognize and interpret shadow patterns, the radiation source must be precisely aligned to the component geometry. This requires careful alignment and calibration of the test system. For uneven material or component thickness, it's important to check the imaging and, if necessary, incorporate additional test angles or radiation sources.