 Alternating current field measurement

Alternating Current Field Measurement (ACFM) is a non-destructive testing (NDT) technique used primarily for the inspection of metallic structures and components. This method is especially effective for detecting surface and near-surface flaws such as cracks, corrosion, and other material discontinuities. ### Principles of ACFM: - **Electrical Principle**: ACFM operates on the principle of electromagnetic induction. It uses an alternating current to generate a magnetic field around a test object.