Vibrating sample magnetometer 2D and 3D magnetization effects associated with different initial magnetization states

Ronald E Lukins

doi:10.1063/1.4973750

Abstract

Differences in VSM magnetization vector rotation associated with various initial magnetization states were demonstrated. Procedures and criteria were developed to select sample orientation and initial magnetization states to allow for the combination of two different 2D measurements runs (with the same field profiles) to generate a dataset that can be representative of actual 3D magnetization rotation. Nickel, cast iron, and low moment magnetic tape media were used to demonstrate these effects using hysteresis and remanent magnetization test sequences. These results can be used to generate 2D and 3D magnetic properties to better characterize magnetic phenomena which are inherently three dimensional. Example applications are magnetic tape-head orientation sensitivity, reinterpretation of 3D coercivity and other standard magnetic properties, and multi-dimensional shielding effectiveness.

Highlights

AND BACKGROUNDMaxwell equations for continuous macroscopic magnetic media “Bertotti (1998)”, using appropriate value averaged of microscopic fields, yield a linear relationship between magnetic field (H), magnetic induction (B), and magnetization (M) vectors as follows: B=H+M (1)For many materials the magnetization vector can be related to the magnetic field through the magnetic susceptibility , M = H (2)where can be represented as a matrix of susceptibility elements
The y moment component for the metal particle tape shows a slight difference for the initial moment vector that was demagnetized compared to the other two initial magnetizations; whereas for the metal evaporated tape the y-components all vary for the first part of the loop
The planar angle (Θ) for the demagnetized initial state again differs from the other two initial states, while for the polar angle (ø), the initial magnetization at -10 kOe flips much faster than the other two initial magnetizations. These results show that the initial magnetization state must be controlled for prior to performing hysteresis or remenant moment measurements

Summary

INTRODUCTION

Maxwell equations for continuous macroscopic magnetic media “Bertotti (1998)”, using appropriate value averaged of microscopic fields, yield a linear relationship between magnetic field (H), magnetic induction (B), and magnetization (M) vectors (in MKS units) as follows: B=H+M (1). , for six different magnetic materials; third is investigate the use of two properly oriented 2D VSM hysteresis (with identical field step profiles) to assemble a 3D phenomenon data set that, for some materials, represent the magnetization rotation in 3 space as the applied field varies “Suzuki (1976), Finegan and Clark (1985), Bernards (1991)”. These 2D and 3D magnetization characterizations more accurately describe and can be better. All testing was performed at 25◦C using a Model 1660 DMS VSM

Test sequence one

Test sequence two

Temperature control and calibration

Magnetization or magnetic moment calibration

RESULTS AND DISCUSSION

CONCLUSIONS