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We have determined the easy axis of magnetization of Fe3C (cementite) using a powder specimen prepared by an electrolytic extraction method. The easy axis is determined to be the c-axis (the shortest axis) of the orthorhombic structure with the space group Pnma. The result is different from the one previously reported by neutron diffraction (b-axis). The magnetic energy difference between the easy axis and the average of other two axes is approximately 400 kJ/m3 at 5 K.

An Fe–55Pd (at.%) alloy exhibits a disorder–order transformation from the A1-type disordered cubic phase to the L10-type ordered tetragonal phase. We have investigated the influence of the magnetocrystalline anisotropy energy on the selective formation of a variant of the ordered phase during heat treatment. We found that the strength of the magnetic field required to produce a single variant decreases from approximately 4 T to approximately 0.4 T when the ordering heat-treatment temperature is decreased from 673 to 603 K. The magnetocrystalline anisotropy energy was evaluated at these temperatures as a function of magnetic field. The nucleation ratio between different variants was evaluated through the magnetocrystalline anisotropy. It is revealed that a single variant state is obtained during the growth process when the nucleation ratio of the dominant variant exceeds approximately 1.1.

Amorphous Ti–36Ni–7Sn (at%) alloy ribbons prepared by melt spinning were annealed at various temperatures for crystallization and then microstructures and transformation behavior were investigated by means of electron microscopy, X-ray diffraction and differential scanning calorimetry. Crystallized Ti–36Ni–7Sn alloy ribbons consisted of Ti3Sn, Ti2Ni and TiNi phases. Size of Ti3Sn phase was in the range of 50–850 nm depending on annealing temperature. Average size of TiNi phase increased from 25 nm to 100 nm with raising annealing temperature from 873 K to 1073 K. Volume fraction of Ti2Ni phase decreased by raising annealing temperature through decomposition reaction of 3Ti2Ni + Sn (solved in TiNi phase) → 3TiNi + Ti3Sn and then Ti2Ni almost disappeared by annealing at 1173 K. The TiNi phase in crystallized Ti–36Ni–7Sn alloy ribbons showed the B2–R–B19′ transformation behavior. DSC peak temperature associated with the B2–R transformation (TR*) decreased from 303 K to 292 K with raising annealing temperature from 973 K to 1173 K, while DSC peak temperature associated with the R–B19′ transformation (Ms*) increased from 187 K to 237 K with raising annealing temperature from 1073 K to 1173 K and thus the temperature gap between TR* and Ms* decreases from 112 K to 55 K.

By annealing Ni film/Li film/Ti–50Ni alloy in O 2 atmosphere, we fabricated a superelastic electrode consisting Ti–LiNiO 2 film as a cathode material and TiNi substrate as a current collector. The electrode with partial shape memory effect and superelasticity exhibited a high operating voltage of 3.7 V and a good reversibility of Li ion. An increased M S of TiNi alloy in the electrode was attributed to a compressive stress imposed by TiO 2 and Li 0.98 Ni 0.7 Ti 0.3 O 1.92 layers.

We have investigated the influence of magnetic field on the precipitation of cementite in the ferrite of an Fe-0.01 mass%C alloy. Four variants of acicular shaped precipitates of cementite form with its long axis parallel to one of α directions of the ferrite. We have confirmed that the volume fraction of each variant is 1/4 unless magnetic field is applied. When a magnetic field of 7 T is applied at 473 K, the variant with lowest magnetocrystalline anisotropy forms preferentially compared with other variants although the former variant has higher magnetic shape anisotropy energy than the latter variants.