Rapid non-destructive testing of weld defects on certain load-bearing platforms using ACFM technology

In view of the limitations of traditional non-destructive testing methods for weld inspection on a specific load-bearing platform in the aerospace sector, this paper proposes a rapid weld defect detection method based on Alternating Current Field Measurement (ACFM) technology. This technique enables the localization and quantitative assessment of weld defects without removing anti-corrosion coatings. First, the principles and unique advantages of ACFM technology are explained. Subsequently, ACFM probe selection and parameter configuration are performed based on the geometric characteristics of the load-bearing platform structure and the inspection environment. ACFM technology is applied to detect weld defects on a decommissioned launch vehicle load-bearing platform, with magnetic particle inspection used for verification to validate the accuracy of ACFM results. Results demonstrate that this method can quantitatively detect weld defects in metallic base materials through non-conductive paint layers up to 3 mm thick. For surface crack defects exceeding 5 mm in length, the detection rate reaches 100%. This technology holds significant importance for ensuring the structural safety of space launch equipment and enhancing inspection and maintenance efficiency.