Characteristics of magnetic parameters of granular samples with various relative length

Abstract

Abstract The experimental data of magnetic flux and induction in ferromagnetic granular samples (filling of balls with 8mm diameter in a cylindrical container with diameter D = 40mm) have been obtained with various relative lengths of samples L/D = 1-16 in a magnetizing field with strength range H = 9.4-47.2kA/m. These data have been used to determine the corresponding dependencies families of magnetic permeability, susceptibility, and magnetization, as well as the demagnetizing factor data of such samples. The absence of magnetic saturation of granular (as opposed to solid) magnetics in the considered range H has been revealed (by analyzing the trend of induction field dependencies and especially magnetization). From the experiment, it is evident that in this range H field dependencies of such parameters, as magnetic permeability and susceptibility demonstrate weakly expressed non-sharp extreme. From the experiment, it is also evident that for the studied samples (as quasisolid magnetics) the transition value L/D=[L/D] = 10-12, i.e., significantly lower than for solid samples, particularly those made of steel. The dependence of demagnetizing factor data on L/D has been obtained for “short” samples (1 ≤ L/D < [L/D]). In addition, eligibility of approximation by exponential expression has been shown for this data.