Abstract
Alternating current field measurement (ACFM) has been widely used to detect and evaluate metal surface cracks. However, the lift-off caused by various attachments significantly affects the accuracy of crack size assessment. In this article, a simple method is proposed to evaluate surface cracks without the limitation of lift-off. The theoretical models of ACFM and the lift-off effect are developed. The influence of lift-off on magnetic field response signals is studied with the aid of the finite-element method (FEM). The ACFM test system is set up, and the experiments are carried out to evaluate surface cracks of different dimensions at different lift-off distances. The test results show that the length and depth of surface cracks can be accurately evaluated at an unknown lift-off distance by the proposed method.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
