The electrical resistivity has been measured on Co–Ni and Co–Cr dilute alloy specimens in the temperature range from 4.2 to 360 K. The deviations from Matthiessen’s rule (DMR) derived from the resistivity data have been analysed in terms of the two current model. It is confirmed that a spin mixing term proportional to T² is the dominant mechanism of DMR at low temperatures. The large value of the residual resistivity in the spin down subband of the Co–Cr alloy is associated with the virtual bound state of spin down electrons of chromium lying close to the Fermi level of the spin down subband of cobalt.

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Molecular dynamics simulation of the molten K_0.8(KCl)_0.2 system has been carried out at 873 K, 973 K and 1173 K. The interionic potentials in this system are based on the linear screening theory with the Ashcroft and the Shaw potential for the electron-cation and the electron-anion interaction, respectively. The pair correlation functions, the self-diffusion coefficients of the component ionic species and size of the aggregate of Cl⁻ ions are derived, and the temperature dependence of these properties is discussed. It is shown that the aggregate of Cl⁻ ions grows with decrease of temperature, and a large and stable aggregate of Cl⁻ ions appears at 873 K.

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An attempt was made to observe in situ early stages of the isothermal martensite formation by a high voltage electron microscope, using Fe–Ni–Mn and Fe–Ni–Mn–C alloys. Observed transformation characteristics are different, in many respects, from those in bulk specimens, but some experimental facts which characterize the isothermal martensitic transformation have been obtained; especially, an observation of the generation of dislocations prior to the martensite nucleation provides direct evidence supporting a rate controlling mechanism proposed by Kajiwara for the isothermal martensitic transformation. It is considered that, in the case of the fcc/bcc (or bct) martensitic transformation, observation of the nucleation stage in thin foil experiments is intrinsically impossible due to the small thickness of specimens even on very favorable experimental conditions.

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Permeation response of hydrogen and deuterium through α-iron under the condition of pressure modulation was measured to determine the diffusion coefficient which contained no surface effects. The diffusion coefficients of hydrogen isotopes are obtained between 500 and 1000 K.
Permeation under hydrogen ion bombardment was also studied to extend the temperature range of diffusion coefficient measurements.
The ratio of the diffusion coefficients of hydrogen isotopes (D_H⁄D_D) depends on the temperature; the value of the ratio approaches unity with increasing temperature. This behavior differs from that of common fcc metals in which the value of the ratio approaches \sqrt2 with increasing temperature. The isotope effect of hydrogen diffusivity in α-iron can not be explained by the classical rate theory, and the quantum-mechanical correction is needed.

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In situ high temperature electron microscopic observations of 1.5 mass%C martensitic steel plates show that at the third stage of tempering a small θ-Fe₃C region is formed at first on the surface of θ′-particle, which is formed below 550 K and composed of microsyntactically intergrown various thin carbide layers, and then grows to a nearly perfect θ-particle at the expense of θ′-particles. At the matrix grain boundary the θ-region is formed at 550 K or lower, while in the grain it is formed at about 700 K. During the tempering, the coalescence and disappearance of θ′-particles take place in a complicated way. Some of the θ-particles in the grain dissolve into the matrix above about 800 K to make other θ-particles grow. The matrix recovery starts at about 700 K. The heat evolution at the third stage, which finishes at 730–750 K, can be ascribed to the transition from θ′-particles to θ-particles and the matrix recovery. In Appendix, high resolution study of planar defects in a θ-particle remaining in a tempered specimen at 870 K is described.

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The structure factors of liquid Zn at 723 K, Sn at 523 K and Bi at 573 K have been determined by neutron diffraction with sufficient accuracy and compared with those of X-ray diffraction. A remarkable difference in the structural information between the two methods is clearly found around the first peak region as well as in the slightly varied peak positions, and it is apparently larger than the experimental errors.
With these facts in mind, a new method evaluating the ion-electron correlation function in liquid metals has been proposed by using the measured structural data of X-rays and neutrons, with the help of theoretical values of the electron-electron correlation function by he Utsumi-Ichimaru scheme. This method has been applied to liquid Zn, Sn and Bi, and the radial distribution function of valence electrons around an ion has been estimated, from which the ionic radius and the schematic diagram of the electron distribution map are obtained. The ionic radii evaluated in this work have been found to agree well with those proposed by Pauling.

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The directional solidification of MgO–ZrO₂ eutectic has been investigated by the Bridgman type method. The melting was conducted using a Mo crucible in an argon atmosphere at the growth rate of 10–20 mm/h. Colony-free structures were obtained at these growth rates. The lamellar morphology as well as the fibrous morphology has been observed in the same sample. The orientation relationship was examined by electron diffraction and was determined as a cube/cube relation for the fibrous morphology. It was observed that the fiber rotated to the matrix within 5°. The orientation relationship for the lamellar morphology was given as (010)ZrO₂//(111)MgO and [100]ZrO₂//[110]MgO. The lamellar interface was almost (010)ZrO₂ which was parallel to (111)MgO.

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The direct analysis of solid metal samples by inductively coupled plasma emission spectrometry has been investigated. An aerosol generator (AG) by a low voltage spark discharge was used for vaporization of metal samples, and the aerosol was introduced into the plasma through an aerosol cyclone. The effect of the length of a transporting tube (stainless steel) was examined. The lengths investigated were 1, 3, 5, 7.5 and 10 m. The spectral intensities lowered, the amounts of aerosol transferred into plasma decreased, and the relative standard deviation of spectral intensities became worse with the increase of the length. In the determination of Co, Cr and V, no phenomenon of selective adhesion to the inner surface of a transporting tube was observed. In the case of tungsten, there was selective adhesion to the inner surface of the tube and selective removal in the aerosol cyclone. However, in the practical analysis there was no problem, since the standard reference materials for calibration were affected in the same way as the samples for analysis were. This method was compared with the low voltage spark emission spectrometric analysis. In the present method, there were no interfering elements, while in the latter several major elements showed spectral interferences, and in the case of preparation of calibration curves for V and W, there were some standard reference materials which were not fit for making the calibration curves. The direct ICP emission spectral method gave excellent straight calibration lines for all the elements such as Mo, W, Co, Si, Mn, Cr, V and Cu under investigation, and showed better accuracy and precision.

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A mathematical description of the variation of normalized concentrations of components in matte during converting has been proposed for a 50 ton converter of a Chinese nickel smelter. Two process parameters, molar ratio of desulfurization to deironization of matte converting, dn_S⁄dn_Fe, and sulfur deficiency fraction of matte, δ_S, which characterize the matte converting process, have been deduced as a function of iron content in matte. Laboratory experiments and plant tests of further deironization of concentrated matte were carried out to obtain a final matte product with an iron content less than 1% and a sulfur content more than 20% by mass.

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