A Static-Sample Magnetometer for Characterizing Weak Magnetic Materials
; Buzio, M. B.
; Pentella, M. P.
Ramos, P. M.
IEEE Transactions on Instrumentation and Measurement Vol. 70, Nº 6003309, pp. 1 - 9, April, 2021.
ISSN (print): 0018-9456
Journal Impact Factor: 1,790 (in 2014)
Digital Object Identifier: 10.1109/TIM.2020.3041823
In this paper, a static-sample magnetometer is presented to measure the relative permeability of weakly magnetic materials. The method consists of scanning the magnetic field inside a dipole magnet by using an NMR teslameter to measure the perturbation of a test specimen on the externally applied field. Then, an inverse problem is used to compute the specimen’s relative permeability. As a case study, the measurement of three different materials with different shapes and dimensions is carried out. The method was validated by measuring the same material by a vibrating sample magnetometry as proposed by the standard ASTM A342/A342M-14. The Monte Carlo evaluated expanded measurement uncertainty of the relative permeability is about 10*4 for all the cases, with a level of confidence of 95 %.