Radiographic Testing Using Gamma Radiation
Gamma radiography uses radioactive isotopes to inspect the internal structure and defects of a component. The attenuation of radiation indicates where defects or changes exist.
Physical-Chemical Mechanism of Action
Gamma radiation consists of high-energy photons that travel through the material. The more atoms in the path that absorb or alter the radiation, the stronger the attenuation. This attenuation is recorded and analyzed.
Metallurgical Relevance & Welding Risks
Radiographic testing is particularly helpful for verifying weld quality, especially in hard-to-reach areas. It can detect porosity, cracks, or changes in material structure that visual inspection methods cannot see. However, handling radioactive isotopes is hazardous and must be strictly regulated.
Workshop Practice & Procedures
• Preparation: Ensure all safety measures are followed. Use protective clothing and respiratory protection.
• Exposure: Position the isotope to directly penetrate the area of the part to be tested.
• Image Capture: Use a detector device to record the radiation attenuation and save it as an image.
• Analysis: Analyze the image with specialized software to identify defects or changes.