Frequency Selection
Frequency selection is the targeted choice of test frequency in eddy current testing to optimize penetration depth and suppress interfering signals. This improves the signal-to-noise ratio.
Physical-Chemical Mechanism of Action
Frequency selection refers to choosing a specific frequency for eddy current testing to achieve particular properties of the material being tested or the test depth. Each frequency has different penetration depths and can therefore be optimized for different materials and test depths.
Metallurgical Relevance & Risks in Welding
Correct frequency selection is crucial for the accuracy of eddy current testing. An incorrect selection can lead to inaccurate results, which in turn leads to errors in the material control process and potential safety risks when using the material.
Workshop Practice & Instructions
For frequency selection in eddy current testing, the following guidelines should be observed:
• Test depth: Choose a frequency that matches the desired test depth. Higher frequencies provide a smaller test depth, lower frequencies provide a larger one.
• Material: Use frequencies that are suitable for the specific material. Some metals require higher frequencies than others.
• Interference signals: Use filters or other methods to suppress interference signals and thus increase the signal-to-noise ratio.