In order to investigate how the Elinvar characteristics of nickel at high temperature are altered by the addition of aluminum and tantalum as a second element, measurements of Young’s moduli at low and high temperatures and thermal expansion at room temperature were made for the binary alloy systems. In either of Ni–Al or the Ni–Ta alloys, the Elinvar characteristics of nickel at high temperature were attenuated with the addition of these elements; Young’s moduli were depressed along the magnetic transformation points. Also, a small minimum of the linear coefficient of thermal expansion was observed to appear near the composition range where the Elinvar characteristics occurred at room temperature.

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Measurements have been made of the magnetization and its hysteresis loop of an Fe–13P–7C amorphous alloy in the form of ribbons. The as-quenched specimen is a typical soft ferromagnet with low coercive force. Application of tensile stress increases the remanence up to about 0.92 times the saturation magnetization. Twisting of the specimen results in the complete squareness of the hysteresis loop. By annealing, the effect of tensile stress on the magnetic properties can be stabilized permanently. A high permeability of the amorphous alloy is obtained by magnetic field-annealing.

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Formation and growth of modulated structure with aging were investigated for Ni-37 at%Cu-8 at%Si and Ni-30 at%Cu-5 at%Si alloys which show a typical modulated structure, by means of transmission electron microscopy, X-ray diffraction and electrical resistivity measurements. The results obtained are as follows: (1) For short time aging, the periodic phase-decomposition of [100] direction was observed and its spacing did not change during short time aging. The solute concentration increased rapidly during this aging period. Thus the behavior of phase decomposition may support Cahn’s spinodal theory. (2) For longer time aging, zone-spacing increased in proportion to t^1⁄4. The growth of zone-spacing takes place in the following way. The zones which are formed by the waves of three [100] directions during short time aging assume the simple cubic lattice type. With a progress of aging the simple cubic structure is changed to the fcc type which is formed by extinction of zones existing in the nearest neighbor site in the simple cubic structure. On further aging, through the same extinction mechanism, the fcc type modulated structure changes into the simple cubic structure in which the spacing of the remaining zones is twice the original simple cubic structure. It is considered that an excellent periodicity and alignment of the zones in the modulated structure is formed through this growth mechanism.

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The stress corrosion cracking test of 70–30 brass specimens with various dislocation arrangements was performed in a 6N ammoniacal aqueous solution containing cupric ions. The results indicate that the specimen with planar arrays of dislocations is not always more susceptible to stress corrosion cracking than that with cellular arrays. And it is suggested that the stress corrosion susceptibility of 70–30 brass is largely dependent on the segregation of solute atoms to lattice imperfections. Stress corrosion phenomenon was also found in Cu–Ti alloys. Stress corrosion susceptibility of Cu–Ti alloys is strongly dependent on aging treatment and both of intergranular and transgranular cracks are found in aged Cu-4%Ti alloy. It is suggested that the increase of stress corrosion susceptibility is due to the local fluctuation of the concentration of solute atoms in the prestrained 70–30 brass and aged Cu–Ti alloys.

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Changes in the structure of Fe(111) and (110) surfaces due to heating in vacuum were investigated by means of LEED and Auger electron spectroscopy. These data indicated that with rising temperature, (110) facets developed in the Fe(111) surface and oxygen and sulfur atoms gathered in each stage around (110) and (111) respectively, resulting in a reconstruction of the surface forming a superlattice. Based on the LEED patterns obtained from the specimens, possible arrangements of the lattice of the oxygen and sulfur atoms in each stage of the surface development were determined.

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The values of activation energy for recrystallization were obtained in hot forged or cold rolled Ni-30%Cu alloy ingot by isothermal annealing. The values obtained were as follows:
64500±900cal/mol for the ST specimen,
67000±900cal/mol for the CT specimen,
56000±900cal/mol for the CR specimen,
65500±900cal/mol for the ER specimen.
ST: Hot forged and recrystallized before cold rolling
CT: Columnar axis was perpendicular with the cold rolling direction
CR: Columnar axis was parallel with the cold rolling direction
ER: Equiaxed zone of ingot

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The growth process of oxide layers in the initial oxidation of 80Ni–20Cr alloy has been studied in the temperature range from 500 to 1000°C in air by means of electron diffraction and X-ray microanalysis.
The oxide film formed in a quite early stage (e.g. at 600°C for 1 min) was found to have a NiO structure, while the amount of Cr in the film was twice as much as that of Ni. By annealing of the stripped oxide film the electron diffraction pattern was changed to sharp strong patterns of Cr₂O₃ containing NiCr₂O₄ and NiO.
X-ray microanalysis of oxide films formed at 600°C for 1∼1080 min showed that the Cr content in the oxide layer increased with oxidation time, whereas the Ni content remained constant.
From the present results the following growth process can be constructed. At the beginning of oxidation, this alloy is oxidized at the alloy composition of 80Ni–20Cr. The oxide crystal structure is of NiO. The Cr content in the oxide film increases by preferential oxidation of Cr at the inner oxide layer during the oxidation. Consequently, the concentration gradient of Cr is built up in the oxide layer, from the composition of NiO at the outer layer to the composition close to Cr₂O₃ at the inner layer. Due to the epitaxial relationship with the outer NiO structure, the oxide continues to be of NiO structure despite an increase in the Cr content at the inner layer. As the oxidation continues, a continuous layer of stable corundum type Cr₂O₃ is formed at the inner layer. Then, the Cr₂O₃ layer acts as protective for oxidation and oxidation rate is controlled by diffusion of Cr through the Cr₂O₃ layer.

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The relations of neighboring Mn atoms, Mn–Mn interatomic distances and valence electron numbers to their magnetic moments and magnetic transformation temperatures in Cl_b-type Mn base compounds have been investigated.
The magnetic interaction of these Cl_b-type compounds is probably dependent upon the type of neighboring Mn atoms. The variation of the Mn–Mn distance of stoichiometric Cl_b-type compounds is found to be closely related to the change in the Curie temperature rather than the saturation magnetic moment per Mn atom. For many Cl_b- and L2₁-type compounds, the relation between the number of valence electron per atom and the ferromagnetic and paramagnetic Curie temperatures are represented by a characteristic curve. The Curie temperatures of Cl_b-type compounds NiMnSb, PtMnSb and PdMnSb in equivalence per chemical formula decreased gradually with increasing Mn–Mn interatomic distance. With increasing Mn–Mn interatomic distance, the paramagnetic Curie temperatures of CuMnSb, PdMnTe and AuMnSb which have one valence electron higher than the aforementioned compounds increased gradually and the transition from antiferromagnetism to weakly ferromagnetism takes place.

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The effects of the growth conditions on the solid-liquid interface shape during the Czochralski growth of Cu crystals have been investigated. It is found that the interface shape is convex towards the melt in all cases, although the degree of the convexity of the interface varies with the growth conditions; the main results are as follows: (1) The degree of interface convexity increases with a decrease of the crystal radius. (2) The degree of interface convexity increases with an increase of the crucible rotation rate. (3) In a shoulder part of the crystal ingot, where its diameter increases, the degree of interface convexity is high, but it changes to a low value in the next part of the ingot where the diameter is constant. (4) The degree of interface convexity is almost independent of the growth rate. (5) A forced convection by Ar gas near the growing interface has little effect on the solid-liquid interface shape.
Moreover, the effect of the degree of the interface convexity on the crystal perfection has been examined. It is shown that the degree of crystal perfection is probably related to the thermal stress which arises from the convexity of the solid-liquid interface.

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The behaviour of interstitial atoms of light elements in the iron lattice are discussed and classified, particularly in regard to their influence on the bonding nature of the iron lattice and their tendency of formation of platelet clusters. According to this general consideration the stress induced clustering of hydrogen atoms is expected in iron and steel, which would cause the hydrogen embrittlement and delayed fracture of the materials.

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