The change in axial ratio c⁄a with composition in AuCu_1−yNi_y, AuCu_1−yPd_y and AuCu_1−yPt_y with Ll₀-type structure was investigated by X-ray diffraction. The axial ratio c⁄a decreased with increasing composition y for AuCu_1−yNi_y (0≤y≤0.16), while it increased with y for AuCu_1−yPd_y (0≤y≤0.24) and AuCu_1−yPt_y (0≤y≤0.06).
The experimental results, together with those published previously for CuAu_1−yNi_y, CuAu_1−yPd_y and CuAu_1−yPt_y, were analyzed in terms of two energies; a repulsive interaction energy between ion cores and an electrostatic energy of ions. Numerical calculation explained qualitatively the observation in all systems, except for AuCu_1−yPt_y.

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Work-hardening behavior of Al–Al₃Ni eutectic composite in Stage II was investigated at various temperatures through observation of tensile deformation and the Bauschinger effect.
The work hardening rate of this material in stage II at temperatures from 293 to 673 K, which was measured by a simple tensile test, decreases with rising temperature. Even at elevated temperatures the contribution of elastic modulus of Al₃Ni fibers to the strain hardening rate is predominant. The matrix of this composite shows a linear work hardening at temperatures from 293 to 673 K, but its contribution to the strain hardening rate of composite is very small.
The mean internal stress and the reversible stress of this composite, obtained by a cyclic tensile loading-unloading test, are consistent with the elastic stress component of the fibers and the reversible stress in the matrix, respectively. This result suggests that the Bauschinger effect in the matrix is very small, even if it exists, and the stress causing the Bauschinger effect is predominantly the elastic component of fibers.

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The models of Wagner and of Blander et al. for dilute solutions of a nonmetal X in binary melts A–B have been improved in the following way. In the PCC model (preferential coordination cluster model), the number of solvent atoms, n, bonded to a solute X is assumed to be smaller than that of solvent atoms, Z, which surround it. In the PBB model (preferential break bond model), it is assumed that Z=n, and strong solvent-solute interactions reduce the strength of the solvent-solvent bonds formed by m of the Z solvent atoms bonded to the solute X by a fractional extent. When the solvent A–B exhibits regular solution behavior, the resulting equations for the activity coefficient of X, γ_x, yield results comparable with those obtained by the previous models. If the interaction between solvents A and B is very strong, the present equations lead exclusively to an abrupt change in γ_x around a particular composition, as demonstrated by the experimental data.

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A Bourdon spoon gauge was employed to measure the vapor pressure of phosphorus between 373 and 1423 K. Between 573 and 973 K, the pressure obeyed the ideal gas law, indicating P₄ to be predominant. Above 1073 K, measured pressures deviated from the law, and the pressures of P₂ and P₄ were separated from each other to calculate the equilibrium constant K_p for these vapor species. Below 475 K, liquid phosphorus was observed to condense, and the measurements yielded the vapor pressure p_p4 over liquid phosphorus. The third law method was employed to calculate ΔH₂₉₈⁰ for the two equilibria and to express K_p and p_p4 in best fit equation of temperature.

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The present study was performed to verify whether a curious anomaly found out in the Zn–Bi system could occur in the Zn–Pb system. Three different methods of emf, sampling and picnometric techniques were employed to attain this purpose.
The obtained results proved that such anomaly occurred also in a like manner in the Zn–Pb system. Temperature dependences of the density behaved irregularly to be indicative of an existence of the structural transformation or local liquid separation in the molten alloys.

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Sound velocity and isobaric specific heat in the molten system Na(NO₂–NO₃) have been measured by the ultrasonic pulse-echo method and by the differential scanning calorimetry method, respectively. With these observed values and an available density, isochoric specific heat, adiabatic and isothermal compressibilities and internal pressure have been derived. These observed and derived properties of the molten system Na(NO₂–NO₃) show a good linearity with concentration. It has been conjectured that such good linearity may not be due to a similarity of ionic radii between NO₂⁻ and NO₃⁻ with comparison between the properties of the systems (Na–K)NO₃, (Na–K)(NO₂–NO₃) and Na(NO₂–NO₃).

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Visually smooth and adherent deposits of molybdenum have been obtained electrolytically on a copper, a nickel, a stainless steel and a molvbdenum substrate in a KF–B₂O₃–Na₂MoO₄ fused salt at temperatures of 1023–l173 K and current densities of 110–1880 A/m² with a molybdenum and a graphite anode.

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The fatigue strength of carbonyl iron compacts sintered at a temperature in the ferrite and austenite ranges and the intergranular fracture (IGF) observed in the fatigue tests were investigated.
The results are as follows:
(1) The fatigue strength of carbonyl iron compacts sintered for 3.6 ks in the temperature range between 1073 K and 1423 K is higher in the ferrite and lower in the austenite field. The endurance limit ratio obtained is in the range between 0.41 and 0.47.
(2) The fatigue strength of specimens sintered isothermally at 1123 K and 1423 K increases gradually with the increase in the sintering time, except that of specimen sintered for 172.8 ks at 1123 K which decreases remarkably.
(3) The mode of fatigue fractured surface for specimens sintered at 1123 K is a mixed trans- and intergranular fracture, while that for specimens sintered at 1423 K is mainly transgranular.
The fraction of IGF increases with the increase in the sintering time at 1123 K and with the decrease in the carbon content.

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