The e.m.f. of the following galvanic cells with a ZrO₂+CaO solid electrolyte has been measured in the temperature range of 850–1050°C in the whole composition range of spinel type solid solutions of Fe₃O₄–ZnFe₂O₄.
(−)Fe₃O₄, Fe₂O₃/ZrO₂+CaO/(Fe₃O₄)_x(ZnFe₂O₄)_1−x, Fe₂O₃(+)
(−)Ni, NiO/ZrO₂+CaO/(Fe₃O₄)_x(ZnFe₂O₄)_1−x, ZnO(+)
The activities of Fe₃O₄ were derived from the e.m.f. according to a new analytical method. In the solid solutions coexisting with the Fe₂O₃, a_Fe3O4 curve shows a small positive deviation from Raoult’s law in the ZnFe₂O₄-rich range, and obeys Raoult’s law in the Fe₃O₄-rich range. In the solid solutions coexisting with ZnO, the a_Fe3O4 curve shows a large positive deviation from Raoult’s law in the whole composition range and a_Fe3O4 has a finite non-zero value in pure ZnFe₂O₄. Equilibrium oxygen partial pressures for the solid solutions coexisting with Fe₂O₃ or ZnO were calculated from the experimental results. These results were compared with published data.

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The kinetic equations of B2 and DO₃ types of ordering in binary alloys were derived by taking into account the mechanism of atomic migration through vacancies within the Bragg-Williams approximation. The kinetic data of ordering in Fe₃Al alloys obtained by X-ray diffraction and measurement of electrical resistivity were treated with the kinetic equations. The variation in the degrees of order obtained by X-ray diffraction with cooling the alloy at various rates is reproduced satisfactorily by solving the equations numerically. The resistivity changes during isothermal annealing after quenching from various temperatures are analysed with the equations to determine the vacancy formation energy, It is expected from the kinetic equations that the B2 type of ordering takes place too rapidly to be prevented by cooling at the rate smaller than 10⁷°C/sec, but that the DO₃ type of ordering takes place slowly enough to be prevented by cooling at the rate of 10³°C/sec.

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The melt spinning of Fe₈₀P₁₆C₃B₁ alloy is carried out by making use of the spinability of glass and a continuous alloy filament, about 5μ in diameter, is produced at a winding speed of 477 m/min.
X-ray and electron diffraction patterns of the filament show diffused broad peaks characteristic of amorphous phases. The crystallization process of the filament is examined and a metastable bcc structure is observed for the filament annealed at 350°C for 30 min and the stable phase of Fe,Fe₃ (C,B) and Fe₃P for the filament annealed at 500°C for 30 min.
The mechanical properties are measured in tension with an Instron type machine for the amorphous filament and the filament annealed at 500°C for 30 min. The brittle behavior is observed for both filaments. The Young’s modulus of the amorphous filament is much lower than that of the crystallized filament. The size effect on the strength of the filament is apparent and the strength in the amorphous state is higher than that in the crystalline state at the same diameter; for example, a tensile strength of 250 kg/mm² for the amorphous filament and 130 kg/mm² for the crystallized filament for a diameter of 4.5μ. Fracture surfaces of the amorphous filament consist of a smooth region produced by shearing and a vein pattern first reported by Leamy et al.

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A general thermodynamic expression has been considered regarding the association in metallic solution. When an associated complex is formed with a chemical unit of A_μB_γ in the A-B binary liquid and its associated solution is approximated as a regular solution, the excess free energy is constructed by three terms of the formation energy of associated complexes, the interaction energy between the complexes and free atoms, and the excess entropy of mixing generated by the existence of associated complexes. Analysis of thermodynamic properties in In–Sb binary and InSb–M (M=Sn, Pb and Bi) quasibinary systems confirmed that the approximation model derived for the thermodynamic expression is satisfactorily applicable in the case of small degrees of association. The theoretical structure factor with regard to the concentration, S_cc (0), is in good agreement with the experimental value in the In–Sb binary system. This means that associated complexes with the composition InSb have a tendency to be surrounded by In atoms.

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A rapid and simple analytical method was investigated for the determination of Pb and Bi in Ni- and Co-base heat-resisting alloys by atomic absorption spectrometry using a heated graphite atomizer. The calibration solutions were used for obtaining the calibration curve by this method. They contained the Ni or Co matrix, a base element of heat-resisting alloys, together with Pb and Bi. Effects of Al, Cr, Zr, Nb, Mo, Ta, and W on the absorbance of Pb and Bi were negligible in Ni or Co solution. The matrix concentration in the calibration solutions corresponded with the total metal concentration in the sample solutions. Lead and Bi in Ni- and Co-base heat-resisting alloys were determined by this method rapidly and precisely. The detection limits in the sample were 0.05 ppm for Pb and 0.1 ppm for Bi, respectively.

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The stress corrosion behavior of AISI Type 304L stainless steel has been investigated in H₂SO₄/NaCl solutions using potentiostatically controlled and dynamically loaded wire specimens at room temperature.
In this study the morphology of attack was varied with potentials such as corrosion potential, active/passive and passive/transpassive transition potentials. The morphologies observed included transgranular stress corrosion cracking, intergranular attack, pitting and general corrosion. The most extensive transgranular cracking was observed near the corrosion potential in 5 mol/l H₂SO₄/0.1 mol/l NaCl solution. In the other solutions transgranular cracking was also observed, but cracks were very shallow and failure was a ductile one.
Stress corrosion morphology in acid aqueous solution containing Cl⁻ ions was very complicated, depending upon a controlled potential and concentration of acid and/or chloride. Stress corrosion cracking proceeded under the condition where the surface film was stable and only slip steps were chemically active.
The existence of various morphologies was consistent with the film break/reformation concept of stress corrosion cracking.

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Stress-corrosion cracking (SCC) of commercial Cu-30%Zn alloy in Mattsson’s solution and an aqueous ammoniacal solution at room temperature, and of 304 stainless steel in 128°C boiling MgCl₂ aqueous solution has been investigated by determining the crack propagation rate (\dotγ) as a function of the strain rate (\dotε), and by observing the fracture surfaces.
For a transgranular cracking environment, \dotγ-\dotε curves showed region I where \dotγ increased with increasing \dotε at slow strain rates and region II where \dotγ was independent of \dotε at high strain rates. For an intergranular cracking environment, the curves showed region I at slow strain rates and region II′ where \dotγ decreased with increasing \dotε at high strain rates.
The region of strain rates where intergranular SCC occurred was narrower than that for transgranular SCC.
Fractographs of the specimens subjected to intergranular cracking showed coarse slip steps. It appeared that these steps originated from corrosion of chemically reactive micro-cracks produced by dislocations with a large Burgers vector near grain boundaries.
A mechanism of intergranular SCC was proposed by considering the results obtained. This supports basically the theory set forth by Robertson and Tetelman.

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The extraction of the metal ions from sulphate and chloride solutions with Versatic Acid 911 and di-(2-ethyl hexyl) phosphoric acid in benzene was investigated in order to clarify the effect of sulphate and chloride ions on the extraction. Sulphate and chloride ions are not extracted into the organic phase, and they affect metal extraction only by forming the complexes with metal ions in the aqueous phase. The extent of the effect on metal extraction is determined by the kind of metal ions and anionic ligands, and the concentration of ligand ions. Therefore, the difference in extraction behaviour may be explained by the complexing ability of the various anionic ligands present in the aqueous phase. Formation constants of the complexes between metal ions and anionic ligands were computed from these distribution data.

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The kinetics of deformation induced martensite reaction was studied in conditions of stress-assisted and strain-induced transformation defined on the basis of the temperature dependence of the flow stress of the alloy. The system was perturbed by either changing grain size or subjecting it to compressive shock-wave (8 GPa). The results indicate that, at a given temperature, a prior shock-loading causes an enhancement of the initial rate of martensite formation while grain refining has the opposite effect. The total amount transformed up to necking is affected in the same way.

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A structural investigation on the α₂ phase of Cu–Al alloys was performed by means of X-ray powder diffraction and electron microscopy. The α₂ phase investigated was obtained by annealing the martensitic state of the alloy for a prolonged time. The electron diffraction pattern of the α₂ phase indicated that the α₂ phase has a one-dimensional long period superlattice (LPS) in agreement with the result obtained previously by other investigators. The change in the period of antiphase with the Al concentration was measured by means of X-ray diffraction, and it was concluded that Sato and Toth’s theory is valid for the α₂ phase of the Cu–Al alloys. An unusual broadening of the line profile which was observed in the X-ray powder pattern of the α₂ phase was analyzed to obtain the tetragonality of the fundamental face-centred lattice. The tetragonality was found to have a value of 1.002∼1.003 and to vary by a small amount with increasing Al content. The dependence of lattice parameters of the phase on the Al concentration was also determined.

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