On the Elastic Moduli of Ferromagnetic Materials. Part V. The ΔE-Effect of Iron Single Crystals at High Temperature (Continued) and the ΔK-Effect

Abstract

In the present Part, continued from Parts III and IV. the effect of temperature upon the form of the SH-H curves (SH is the elastic elongation of the magnetic origin in a magnetic fie:d H) in the principal directions is studied. The SH-H curves in the directions of [110] and [111]. deduced in Part III, are modified under the assumption proposed in Part IV, viz. the magnetic moments of the elementary domains are distributed around one of the directions of minimum ∈m (the thermodynamical potential of an elementary domain). It is found by numerical calculation that .SH obtained is always positive and continuous (differing from the results obtained in Part III) and the calculated SH-H curves agree with experimental results. ΔK-effect. The change in the rigidity modulus with magnetization is discussed. It is found that TH=0(=(1/KH=0-1/KH=∞)) is a linear function of 3Γ=3(β₂²β₃²+β₃²β₁²+β₁²β₂²), where K is the rigidity modulus and (β₁, β₂, β₃) the orientation of a crystal, and it is also proved that TH=0 can be expressed in terms of SH=0