Shadow Projection Testing
Shadow projection testing is an optical measuring method where structured light is projected onto the part and deviations are evaluated optically. It enables fast shape and flatness checks.
Physical-Chemical Mechanism of Action
Shadow projection testing uses structured light sources to project sharp shadows onto the component surface. These shadows are then evaluated with an optical sensor or microscope. Deviations in surface shape or contour produce different shadow patterns, which are easy to recognize.
Metallurgical Relevance & Welding Risks
Shadow projection testing is especially helpful for checking weld microstructure and surfaces. It can quickly detect cracks, unevenness, or deformations before they become bigger problems. However, incorrect settings of the light pattern or evaluation can lead to false positive or negative results, jeopardizing quality assurance.
Workshop Practice & Action Items
For accurate shadow projection testing, the component must be clean and dry. The light source must be set to produce sharp shadows. The distance between the light source and the component as well as the evaluation method must be precise. In doubtful cases, additional testing methods like ultrasonic or X-ray should be applied.