What is the name of the crack test strategy that uses metal filings?

The test strategy that uses metal filings is known as the Magnaflux process. This method is primarily utilized for detecting surface and near-surface cracks in ferromagnetic materials. In this technique, a magnetic field is applied to the part being inspected, and when metal filings or magnetic particles are introduced, they will accumulate at any discontinuities or cracks in the material. This accumulation creates a visible indication that can be easily detected by the inspector. The effectiveness of this method lies in its ability to provide quick visual feedback on the integrity of metal components without requiring extensive disassembly or additional preparation.

Other methods listed, such as the hot air test, hot tank test, and dye penetrant, are different types of non-destructive testing techniques used for specific applications but do not involve the use of metal filings. The hot air test typically assesses gasket integrity by checking for air leaks, while the hot tank test cleans components in a heated solution and evaluates for any residual contaminants. Dye penetrant testing involves applying a dye solution to detect flaws after it is drawn into imperfections, but again, it does not involve metal filings and lacks the specific magnetic characteristics leveraged in the Magnaflux process.