Surface roughness affects the magnetic non-destructive testing methods and limits their applicability for testing deeper material regions. This paper presents the results of an experimental study targeting nuclear reactor materials. Samples made of nuclear reactor vessel steel were fabricated with various manufacturing parameters to produce different surface roughness conditions and their describing parameters were determined by a standard measuring device. Magnetic measurements were performed on these samples, series of permeability loops were recorded by the help of a magnetizing yoke attached to the sample surface. Good monotonous correlation was found between the surface roughness parameters and the obtained magnetic characteristics. It is also shown that by applying an adequately chosen nonmagnetic spacer, which is placed between the magnetizing yoke and sample surface, the disturbing influence of the surface roughness can be significantly reduced. This way, even the degradation of samples having different surface conditions can be reliably determined.
|Number of pages||9|
|Journal||GJAETS - Global Journal of Advanced Engineering Technologies and Sciences|
|State||Published - 31 Dec 2019|