Magnetocrystalline anisotropy and magnetostriction of Fe-Si-Al (Sendust) single crystals

The magnetocrystalline anisotropy constant, K₁ and the magnetostriction constants, λ₁₀₀ and λ₁₁₁ for the Sendust alloys were determined at 300 K in the composition region, 7.5–11.0 wt%Si, 4.0–7.0 wt%Al, bal. Fe. The line of K₁ = 0 in the Fe-Si-Al alloy system was found to lie around 7.0–9.5 wt%Si, 5.5 wt%Al, bal.Fe and 9.5 wt%Si, 5.5–7.0 wt%Al bal.Fe compositions. The line of λ_s = 0 was also determined as a function of Fe, Si and Al contents. Both lines of K₁ = 0 and λ_s = 0 intersect at the composition, 9.6 wt%Si, 5.5 wt%Al, bal.Fe. This alloy composition is close to those for alloys with high initial and maximum permeabilities. The line of K₁ = 0 determined by the present experiment is found to be different from that of Zaimovsky and Selissky. The line of λ_s = 0 is similar to their results.