Abstract:
In order to detect the surface and subsurface defects in steel plate of ferromagnetic materials, the pulsed magnetic flux leakage(PMFL) technique was adopted. The detection system is designed for steel plate based on the pulsed magnetic flux leakage(PMFL) technique. When steel plate defect is detected, signal characteristic about defect by magnetically saturating the plate by the way of pulsed excitation is analyzed. The signal voltage peak value and the voltage valley value synchronous curve discrimination flaw method are adopted in this study. The program for the discrimination of surface and subsurface defects in steel plate based on the labview software has been finished. Under the laboratory condition, the examination steel plate with machined rectangular slots is achieved by using the designed scheme. The result indicated that the flaw detection by synchronous curve discrimination flaw method based on pulsed magnetic flux leakage technology was realized on the steel plate.