Various techniques for the production of intense magnetic fields are reviewed in this short note, with geater emphasis on the machine installed once at the Research Institute for Iron, Steel and Other Metals (RIISOM), Tohoku University; since it utilizes a mercury rectifier set as the DC power source, the device for the prevention of pulsation in the obtained DC current is described, together with some pictures showing the waveforms of the pulsation. Results of the achievements at the magnetic field produced by the machine of RIISOM are shown: The magnetocrystalline nature of the compound Fe₇S₈ or Fe₇Se₈ and the magnetic field induced phase transition in the case of α-hematite crystal are discussed in detail.

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The exo-electron emission from metal surfaces subjected to repeated stresses has been studied using an electron-multiplier counting system, and the environmental effects on fatigue strength are discussed from the viewpoint of exo-electron emission.
The exo-electrons from metal surfaces are sharply increased by repeated stresses and take a maximum value at a fixed number of cycles (N_emax). Thereafter the number of emitted electrons gradually decreases and becomes almost constant. The decay of the emission rate after termination of stress repetitions is very fast, its half life being shorter than 1 s. The decay behaviors at cycle numbers before and after N_emax are different; the decay is markedly fast at the beginning of fatigue cycles. The decay of the emission rate from a surface subjected to fatigue damage is, however, smaller than that from a mechanically processed surface. The pulse height distribution of emitted electrons is hardly affected by the progress of fatigue damage. However, sufficient allowances should be made for the role of exo-electrons in the environmental effects on the fatigue strength, in view of the energy height of exo-electrons. The number of exo-electrons per cycle increases markedly with increasing stress cycle frequency.

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The paper discusses a correlation between the diffusion behaviour and the entropy of fusion. It is shown that if the entropy of fusion is equal to or smaller than 6.70 J·mol⁻¹·K⁻¹, the metal is likely to show an anomaly in its diffusion behaviour.

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Upon reversed straining of a pre-strained aluminium at high temperatures, there appears a strain region where plastic deformation proceeds at an approximately constant stress level, and the subgrain structures developed by pre-straining become loosened once and then new subgrain structures characteristic of the reversed straining are formed. In the present experiment polycrystalline aluminium specimens were subjected to a special type of cyclic straining at high temperatures where such a strain region appears.
The amount of strain and the stress level in such a strain region and the ratio of the yield stress upon stress reversal to the pre-stress level decreased with the progress of the cyclic straining. These facts suggest that the stability of dislocation structures upon stress reversal gradually increases, that is, the tendency to undergo changes due to the stress reversal is reduced as the cyclic straining progresses. Transmission electron microscopy showed that the increase in the stability of dislocation structures is caused by the decrease in density of isolated dislocations and also by the change of sub-boundaries from an unstable ill-defined state to a stable well-defined one.

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The magnetic susceptibility was measured for the ζ-phase alloys in Ag–In, Ag–Sn, Au–In, and Au–Sn systems to study the electronic structure of the hexagonal ζ-phase alloys. Discussions are given in comparison with experimental results on lattice parameter, electronic specific heat, and the other properties previously obtained. The situation of electron-overlap and zone-contact in these alloys are interpreted.

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The lattice rotation and operative slip systems at each deformation stage were examined by tensile testing at various temperatures from 77 to 1073 K to make clear the contribution of secondary slip systems to the plastic deformation of Ni₃Al single crystals. The overshooting phenomena were observed below 673 K, and after the overshooting the conjugate slip system operated below 296 K. The contribution of secondary slip systems to deformation was small at low temperature, but increased with increasing strain and temperature. Although the work hardening rate showed the positive temperature dependence, the latent hardening did the negative one. The work hardening of Ni₃Al consists of two mechanisms; namely, one is the orientation and temperature dependent one, which causes the positive temperature dependence by the Kear-Wilsdorf mechanism and has no direct bearing on the latent hardening and the other is independent of the positive temperature dependence, which contributes to the latent hardening.

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Distribution behavior of minor elements has important implications for copper making processes. In this article, the experimental results of the distribution of silver, nickel, cobalt, lead, antimony and arsenic among the three melts of copper, white metal and silica-saturated iron silicate slag are described.
The melting experiments were carried out at 1300°C under controlled SO₂ partial pressures varying from 0.7 to 20 kPa which are approximately proportional to the O₂ pressures.
The distribution ratios for an element X, defined as,
L_x^c⁄s=%X in metal/%X in slag
L_x^c⁄w=%X in metal/%X in white metal
L_x^w⁄s=%X in white metal/%X in slag
can be arranged in the following orders:
L^c⁄s: As, (Ag)>Sb>Ni>Pb>Co
L^c⁄w: As>Sb>Pb, Ni, (Ag)>Co
L^w⁄s: (Ag)>As>Sb>Ni>Pb>Co.
Thus, the impurity elements in this study can be grouped into three classes according to distribution tendencies: As and Sb are highly concentrated in the metal, Co is highly concentrated in the slag, and Ni and Pb are distributed among all three melts in rather similar concentrations. The distribution ratios of the present study generally agree with previous experimental data obtained for simplified two-melt systems. An oxidic dissolution of such forms as NiO, PbO and CoO in the slag is reasonably acceptable, while the possibility of metallic dissolution of Ag, As, Sb and Ni in the slag cannot be denied.

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A rapid and simple analytical method has been developed for the determination of sub-ppm levels of Ag in Ni- and Co-base heat-resisting alloys by graphite furnace atomic absorption spectrometry. Nickel or Co, a base element of heat-resisting alloys, did not affect the absorbance of Ag. The effects of the other elements and acids on the absorbance of Ag were also studied. As a result, the acid solutions of Ag were used as the calibration solutions for the determination of sub-ppm levels of Ag in complex heat-resisting alloys. The results obtained by the calibration curve method agreed well with those by the standard addition method. The detection limit of Ag was 0.005 ppm in the sample by the method described. This method, however, can not be applied for the determination of Ag in Co-base heat-resisting alloys containing large quantities of Al and Ti because of the interferences.

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Mechanical properties of high purity irons were investigated by tensile testing at temperatures from room temperature down to 4.2 K. Specimens with the residual resistivity ratio (RRR_H) of 1800 were brittle and fractured at grain boundaries at 4.2 K. Specimens with RRR_H of 3600, of which the grain structure was almost of the bamboo type, were deformed by slip and often showed complete ductile fracture even at 4.2 K. This is the first observation of slip at 4.2 K without pre-straining at high temperatures in a coarse-grained iron. Specimens with RRR_H of 5000, of which the grain structure was of a well-developed bamboo type, cleaved at 4.2 K, and never showed grain boundary fracture.
Some plastic properties were investigated on specimens with RRR_H of 3600 and 6000. Careful comparison of the results with those reported by other investigators shows that the present specimens are pure enough to reveal some of the intrinsic plastic properties of iron. The yield stress as a function of temperature and the strain rate sensitivity of the flow stress at various temperatures obtained with the present specimens may be considered to be characteristic of iron.

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Low frequency internal friction measurements have been performed on vanadium-deuterium alloys over a temperature range from −190 to 300°C. The terminal solubility of deuterium in vanadium is found to increase by the addition of a small amount of oxygen. The binding energy of deuterium to oxygen has been estimated to be about 0.10 eV.
It has been found that, besides the main precipitation peak, a small peak gradually develops at a lower temperature with the repetition of measurements or thermal cyclings. Since torsional deformation also introduces a peak at the same temperature, the peak is identified as due to dislocations punched out from deuteride precipitates. The main precipitation peak is found to consist of two components: the transient and the equilibrium components. The transient component increases with the increase in the cooling or heating rate, and is inversely proportional to measuring frequencies. The transient internal friction is believed to be associated with the formation or dissolution of hydride precipitates as proposed by Köster and his coworkers for a damping peak in Ti–H alloys.

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