Anisotropic Magnetoresistance (AMR) Magnetometers

A novel electromagnetic apparatus for in-situ synchrotron X-ray imaging study of the separation of phases in metal solidification

“…7 represents the correlation between the separation distance and the mean radius of the magnetic coils ( R MEAN ). According to the Biot-Savart Law [31] , the optimal mid-plane separation distance between the magnetic coils is equal to its mean radius ( x:R MEAN = 1:1), similar to a Helmholtz-type configuration. However, the simulated results did not agree completely with the Biot-Savart Law as it was clearly demonstrated in Fig.…”

“…The theoretical calculations were numerically solved by using the Biot-Savart Law [31] . For a pair of identical coils separated by an arbitrary distance, the total magnetic flux density can be defined as the superposition of the magnetic flux density contributions from each coil at each discrete position along the symmetrical axis of the magnetic coils, respectively, and can be expressed as: where µ 0 is the permeability of free space (H/m), N is the number of turns in each magnetic coil, I is the current passing through the magnetic coils (A), R MEAN is the mean radius of the magnetic coil windings (m), z is the position along the symmetrical axis of the magnetic coils (m), and x is the mid-plane separation distance between the magnetic coil pair (m).…”