Magnetostrictive Materials

MAELASviewer: An Online Tool to Visualize Magnetostriction

“…In this section, we provide a brief introduction to the equations that describe the field-induced magnetostriction (Joule effect and Wiedemann effect), which are implemented in the app MAELASviewer. A more detailed discussion about this topic can be found in [7,[9][10][11][12][13]].…”

“…It is given by the relative length change (l − l 0 )/l 0 = ∆l/l 0 , where l 0 is the initial length of a demagnetized material along a measuring direction β (|β| = 1), and l is the final length along the same direction β when the system is magnetized along the direction α (|α| = 1), see Figure 1. For instance, the relative length change for a cubic single crystal system (point groups 432,43m, m3m) can be written as [9] ∆l…”

“…This strain tensor contains three magnetostriction symmetries or normal strain modes for a cube. Namely, a volume change is given by λ α that does not depend on magnetization direction, while normal and shear deformations are related to λ 001 and λ 111 , respectively [9,10]. In practice, Equation 5 [13]) induced by the Joule effect (without volume magnetostriction λ α = 0) for three simple geometries: cube, cylinder, and sphere with characteristic length 1µm.…”

Overview of Magnetostrictive Sensor Technology

“…Let's now find the values of the Bethe-Slater parameters that simulate magnetostriction. The magnetoelastic energy for cubic systems (point groups 432,43m, m3m) reads 34,35 H cub…”

“…In this case we need the values of the anisotropic magnetoelastic constants b 1 and b 2 . These constants are related to the magnetostrictive coefficients (λ 001 and λ 111 ) and elastic constants (c i j ) via 34,35…”