A method for minimizing the effect of indications caused by gradual dimensional changes is to:

In eddy current testing, the technique relies on detecting changes in the electromagnetic field caused by flaws or discontinuities within a conductive material. Gradual dimensional changes, such as wear or material thinning, can produce indications that might mask or confuse the results when assessing for more significant flaws.

Incorporating a high-pass filter in the eddy current test equipment serves to alleviate this issue effectively. High-pass filters are designed to allow high-frequency signals to pass through while attenuating lower-frequency signals. Since gradual dimensional changes typically occur at lower frequencies, the high-pass filter diminishes their impact, thus enhancing the detection of higher-frequency signals which are more representative of actual defects.

This capability is crucial because it helps maintain the sensitivity of the eddy current test to genuine defects while minimizing interference from gradual changes in dimensions, enabling more accurate assessments of the material's condition.