Magnetoelastic Villari effect in Mn–Zn ferrites

Magnetoelastic Villari Effect in Structural Steel Magnetized in the Rayleigh Region

“…For low values of the tensile stress σ T the value B m is increasing up to the maximum value and then starts to decrease. The stress value corresponding to the maximum of B m is known as Villari reversal point [3] (140 MPa for C45 steel and 120 MPa for 13CrMo4-5 steel). The observed phenomenon becomes stronger with increasing value of magnetizing field amplitude H m .…”

“…One of the several magnetomechanical effects, besides magnetostriction or Wiedemann and Matteucci effects, is magnetoelastic Villari effect discovered by Emilio Villari in 1865 [1][2][3].…”

“…Magnetoelastic Villari effect is physical phenomenon involving change of magnetic state and properties of the magnetized ferromagnetic material under the influence of mechanical stress applied to the material [3,4]. When the sample of the material is subjected to the mechanical stress, changes of magnetic flux density within the material and relative magnetic permeability of the material can be observed.…”

Stress-Induced Anisotropy and Stress Dependence of Saturation Magnetostriction in the Jiles-Atherton-Sablik Model of the Magnetoelastic Villari Effect

“…In this step, parameters a, k, c, M s were the same as for the stress-free sample. However, influence of stresses was incorporated by consideration of the effective magnetizing field He stress dependence, and the anhysteretic magnetization , influencing the results of modelling by equations (1) and (4) together with (11). It should be indicated that calculations in this step were also made simultaneously for 4 hysteresis loops measured for different magnetizing field amplitudes.…”

“…If the value of this product is significantly negative, the decrease of flux density B under stresses σ is observed. On the other hand, for positive value of product lsσ, the increase of flux density B was observed, up to the maximum, called magnetoelastic Villari point [11]. It should be indicated, that quantitative explanation of appearance of the magnetoelastic Villari point on B(σ) characteristics was not presented previously.…”