Dry Magnetic Particle Inspection
Dry magnetic particle testing is a method for crack detection on ferromagnetic materials. Dry particles are sprinkled onto the pre-magnetized part, and leakage fields attract the particles to flaws, which then become visible.
Physicochemical mechanism of action
Magnetic particle dry testing uses a magnetic leakage field. Fine magnetizable dry particles are sprinkled onto the pre-magnetized component. At flaws, such as cracks or damage, local changes in the magnetic field occur, which attract the particles and make them visible.
Metallurgical relevance & welding risks
This test is especially important after welding operations to detect cracks or incomplete weld areas. Failure to detect can lead to further damage and dangerous situations.
Workshop practice & instructions
1. Pre-magnetize the component with a fixed magnetic field.
2. Sprinkle dry particles onto the component.
3. Inspect the component under a light microscope and identify flaws.