One Kind of Green New Method for Detection of Inside Layer Cracks of Aircraft Multilayer Structures

To address the technical challenges in detecting internal cracks within aircraft metallic multilayer structures, we have employed the environmentally friendly detection technique of remote-field eddy current (RFEC). Through theoretical analysis and experimental research, we have analyzed influencing factors such as frequency and phase, designed detection probes and reference blocks, and conducted research on the capability of detecting concealed defects within thick structures (greater than 10 mm). By testing the reference blocks, we have studied the changes in phase and amplitude caused by variations in frequency and damage, gaining insights into the detection capabilities and applicable scope of this method. Ultimately, we have obtained an effective method for detecting internal cracks within different thickness layers of metallic multilayer structures.