It has been shown on the dephosphorization of liquid iron that the values of logγ_P2O5 or log (γ_P2O5⁄γ_FeO⁵) at 1873 K calculated from the data independently investigated and recently reported are closely related to those of the theoretical optical basicity for each slag, and these relations can be expressed in a simple single line for the case, in which slag constituents are lime, sodium oxide and several other materials. The symbol “γ” signifies the activity coefficient of slag components in mole fraction unit. The relation between the phosphate capacity and γ_P2O5 or optical basicity was also discussed. The phosphorus distribution between eleven kinds of slags and liquid Cu–P alloys given by Young and Floridis was analysed by the same way. It would be possible by calculation to estimate a slag composition suitable for dephosphorization, having high theoretical optical basicity.

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The effect of hydrogen absorption on the hyperfine field of iron in an amorphous Fe₉₁Zr₉ alloy is investigated by the Mössbauer effect. The Curie temperature of the alloy variously treated is measured by the thermal scan method, and its values are lower than those obtained by means of magnetic measurements, which suggests that the ferromagnetic state of Fe atoms in the amorphous alloy is unstable and readily affected by external magnetic fields used in the magnetic measurements. The hyperfine field distribution indicates that the infused hydrogen atoms migrate to Zr atoms to form Zr–H bonds and weaken the pre-existing Zr–Fe interaction, which results in the increase of the Curie temperature and the averaged hyperfine field.

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The antiphase domain boundaries inherited from the parent β₁-phase by the 18R copper-based martensites are analysed. The displacement vectors of these boundaries in the 18R structure are calculated based on the lattice correspondence between the parent and martensite structures. The vectors thus obtained, 1/4⟨210⟩_18R and 1/2⟨010⟩_18R, are verified by TEM contrast analysis to correctly define the antiphase domain boundaries present in martensite.

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For the purpose of making clear the mechanism of high temperature deformation of dispersion strengthened alloys, the deformation behavior of Cu–Al₂O₃ alloy single crystals of ⟨001⟩ orientation has been studied with particular attention paid to the effect of the particle distribution, i.e., the particle diameter, d, and spacing, λ. These alloys were prepared by the internal oxidation technique. The volume fraction of Al₂O₃ in the alloys was between 0.2 and 0.8%, and d and λ were in the range of 31–64 nm and 485–815 nm, respectively. The crystals were tested in tension at temperatures between 823 and 923 K and in the initial strain rate range from 10⁻⁵ to 10⁻³ s⁻¹. The main results are summarized as follows: (1) The steady-state deformation appears after small amounts of deformation. The specimen axis hardly rotates during tensile deformation. These facts are ascribed to the operation of multiple slip from the beginning of deformation. (2) The strain rate in the steady-state deformation is represented as a power of stress normalized by the Young’s modulus. Values of the stress exponent and the activation energy for high temperature deformation are 7–9 and about 196 kJ·mol⁻¹, respectively. The latter is close to that for self-diffusion in copper. The flow stress mainly consists of the internal stress. These results suggest that the high temperature deformation of Cu–Al₂O₃ alloys is controlled by a recovery process. (3) The deformation behavior of these alloys depends on the particle distribution rather than on the volume fraction of the oxide particles. The strain rate at a given stress increases with a decrease in d and an increase in λ. (4) The stress and particle distribution dependences of the strain rate in the steady-state deformation of Cu–Al₂O₃ alloys have been discussed on the basis of creep models so far proposed for dispersion strengthened alloys. The local climb model seems to be adequate to the creep of these alloys.

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The net dissolution rate at dislocation sites on the Cu (111) surface etched in Young’s etchant (1 kmol·m⁻³(NH₄)₂S₂O₈, 6 kmol·m⁻³NH₄OH, 0.3 kmol·m⁻³NH₄Br) has been determined from measurements of the dissolved thickness of the matrix surface as well as the three-dimensional size of dislocation etch pits. The etch pit size was measured by a replica electron microscopy. After etching time of 5 s, the width and depth of the etch pits increased at constant rates of \doth and \dotd, respectively, leaving the side slope unchanged. The dissolved thickness of the matrix surface was determined by an interferometric measurement of the step height which was produced along the boundary between the masked surface and the exposed surface. It was found that the matrix surface dissolved also at a constant rate \dots after 5 s etching. The net dissolution rate normal to the surface at a dislocation site, v_d, and that parallel to the surface, v_h, were estimated to be 1.7 times as large as the measured growth rates of etch pits \dotd and \doth, respectively. This fact indicates that dissolution of the matrix surface must not be neglected in describing the dissolution at dislocation sites. Using the values of v_d, v_h and \dots, the nucleation rates of two-dimensional etch pit nuclei at dislocation sites and matrix surface were obtained as 2.9×10² s⁻¹ per dislocation and 8.7×10⁶ μm⁻²·s⁻¹, respectively.

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Visually smooth and adherent deposits of molybdenum have been obtained electrolytically on a copper, a nickel and a molybdenum substrate in a KF-B₂O₃–K₂MoO₄ fused salt at temperatures of 1023–1173 K and current densities of 110–990 A/m² with a molybdenum or a graphite anode.

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A study of the thermodynamics of the liquid alloy systems Cu–Sn and Cu–Cr has been made with the combination of Knudsen cell and quadrupole mass spectrometer. From the data obtained, the activities in the liquid Cu–Sn and Cu–Cr systems, and the heats of mixing in the liquid Cu–Sn system were calculated.
The activities and the heats of mixing for Cu–Sn alloys showed a good agreement with those of other investigators.
The activity of Cr in Cu–Cr alloys showed a large positive deviation from Raoult’s law. The liquidus line of the Cu–Cr system in the Cu-rich concentration range was determined from the break points of the ion current ratios in the mass spectrometric measurements as well as the differential thermal analysis.

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The present study was carried out in order to find out a rule controlling the heat of mixing of liquid alloys.
The bonding-parameter B of elements was evaluated based on the rigid rule on alloying. Values of the heat of mixing of total 138 alloy systems were regulated with success by values of the parameter. The relations between values of ΔH_0.5^M and absolute values of ΔB were essentially divided into the two kinds of parabolic and linear forms. It was thus made clear theoretically that the parameter B had the covalent and metallic characters.

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Magnetic properties, the thermal expansion, the lattice constants, the hardness and the workability were measured for Mn-22%Ge based ε phase ternary alloys containing transition metals in groups IVA, VA and VIA of the periodic table, when they were cooled at various rates after homogenizing at 1100 K for 10.8 ks.
The magnetizations of the Mn-22%Ge based ternary alloys show a temperature variation similar to that of the Mn-22%Ge binary alloy and an abrupt decrease near the Néel point T_N. The ternary alloys also indicate a minimum in the electrical resistivity at T_N. The Néel point of the ε phase moves toward the lower temperature side with an increase in the concentration of the third element. The transformation from ε to ε₁ does not occur readily by addition of a few percent of the third elements, keeping the nature of the binary alloy system.
In the thermal expansion curves of the Mn-22%Ge based ternary alloys there appears a minimum corresponding to the Néel point of the ε phase, showing the Invar characteristics. The thermal expansion coefficient of the ternary alloys in the vicinity of room temperature decreases at first with the addition of the third element, and then appears to increase to a positive value after passing through zero or a small negative minimum value. The spontaneous volume magnetostriction of a Mn-22%Ge-4%Cr alloy at 77 K is 1.3×10⁻², and the value is less affected by the addition of a few percent of Cr. The Vickers hardness of the ternary alloys shows a smaller value than that of the Mn-Ge binary alloys.

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