Special features of diagnostics of magnetic properties of “pipe-layer” chains of spheres

Abstract

Circuit sensor contours created by using the technology of printed circuit boards and placed between spheres of radius R that are in contact allow measuring magnetic (micro-)fluxes Φc over the cores of different radii rc in a magnetized chain of spheres, which are basic elements of a granular medium. The main goal is to obtain information about the magnetic properties of the “pipe-layers” of a magnetized chain of spheres as a quasi-continuous magnet by virtue of the fact that such step-by-step data Φc can also be used to directly judge the step-by-step changes in magnetic fluxes along the “pipe-layers” (limited by adjacent circuit sensors). According to the data Φc, measured using eight sensors (from rc/R = 0.2 to rc/R = 0.9 at steps of 0.1), magnetic fluxes Φp were obtained along seven thin “pipe-layers” of different relative radii rp/R (from 0.25 to 0.85). The Φp data were obtained using chains in which the number of spheres (from 2 to 12) and the intensity of the magnetizing field varied (from 10 to 55 kA/m). The induction values in each of the “pipe-layers” were found and characterized. The values of their magnetic permeability were also found, which reflect the magnitude of the excess field intensity between the granules in comparison with the intensity of the magnetization field, which is of fundamental importance, for example, in matters of fine magnetic separation.