What information does the phase angle provide in defect characterization?

In defect characterization, the phase angle plays a crucial role in interpreting the results of electromagnetic testing techniques, such as eddy current testing. The phase angle represents the phase difference between the induced eddy currents and the alternating current used in the test. This information is essential because it provides insights into both the electrical conductivity and the magnetic permeability of the material being tested.

When it comes to classifying and sizing defects, the phase angle allows practitioners to differentiate between various types of flaws and assess their characteristics. For instance, different defects may exhibit varying phase angles based on their geometry, material properties, and the nature of the electrical signals they support. By analyzing the phase angle along with the amplitude of the response, technicians can enhance their insights, leading to a better understanding of the defect’s depth, shape, and size. This dual analysis is vital for effective defect characterization, making the relationship between phase angle and defect classification and sizing particularly important in non-destructive testing methodologies.