Influence of Surface Roughness on Magnetic Particle Inspection

Magnetic particle testing has been widely used in non-destruction testing of ferromagnetic materials for detecting defects at or near the surface . A rough surface could give rise to the accumulation of the magnetic powder, leading to excessive background which would make the defects harder to recognize and finally cause the missing inspection or wrong results. Analysis about the relationship between surface roughness and magnetic flux leakage of the crack was put forward by establishing models in this paper. The qualitative analysis indicated that surface roughness could influence the reliability of magnetic particle testing to some extent.