It is known that a slow cooled iron-aluminium alloy containing about 12% aluminium has a high permeability. The study of this report was carried out with the intention of investigating how the magnetic properties such as initial and maximum permeabilities are changed when a part of aluminium of this iron-aluminium alloy is substituted by silicon. The iron-aluminium-silicon alloys containing 8 to 13% aluminium and 0 to 4% silicon were melted in vacuum in a high frequency furnace, and the casts were hot rolled into sheets, about 1 mm in thickness, in order to prepare ring-shape specimens. Magnetic properties of these annealed specimens were measured. Consequently, it was found that there existed a high maximum permeability (about 20,000) range in the vicinity of the composition of 88% iron and 0 to 2% silicon, and a very high permeability (initial permeability μ₀=3,000∼5,000 and maximum permeability μ_m=40,000∼50,000) range in the vicinity of the composition of 9% aluminium and 3% silicon. Vickers hardness of the alloys near the composition that has the highest permeability is about 360, which indicates that these alloys are the hardest among the high permeability alloys found at present.

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Practical problems concerning the application of our previously reported spectrochemical method for routine industrial analysis were studied. The differences and variation of the components between the sponge titanium sample solution and the spectrochemical standard solution of titanium tetrachloride and hydrochloric acid, and the evaporation of impurity elements while titanium sponge was dissolved were negligible. The change in the percentage of Si in the spectrochemical standard solution while standing was found by observation of relative intensity for 6 months, and correction procedures are proposed. Various physical properties of carbon electrodes for spectrochemical analysis were evaluated. The effect of the quality of carbon electrodes on the analytical accuracy and precision are described. Finally, some methods for increasing the analytical range are described.

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The internal friction at higher temperatures before Ac₁ transformation in 0.09, 0.38, and 0.85% carbon steels was measured as a function of temperature, using a torsion pendulum with a frequency of vibration of about 1.9 cycles per second. The internal friction curves in 0.85% carbon steels do not show a peak but continue to rise with the rise of measuring temperature from about 400°C. The activation energy of the process causing the anelastic behaviour was found to be 59,000 to 64,000 calories per mole. The internal friction at a given temperature increases with an increase of the amount of carbide in steels. In recrystallized and tempered steels, the internal friction curves shift toward higher temperatures with the rise of annealing temperature. In addition, the internal friction at a given temperature in fully recrystallized and tempered steels is considerably greater than that in steel annealed fully at above A₃₋₁. Such behaviours are interpreted in terms of the concept of the coupled relaxations of an irregular network of interfaces.

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Interaction parameters of alloying elements in molten iron were calculated with statistical thermodynamics by using relatively simple models. The interaction parameter ε_C^(B) between a substitutional solute B and a substitutional solute C is given by using the interchange energy W as follows:
ε_C^(B)={−W_AB+W_BC−W_AC}⁄RT
and that between a substitutional solute B and a interstitial solute C is given by
ε_C^(B)={W_BC−W_AC}⁄RT
The interchange energies in the above equations were estimated from the modified Mott’s equation,
W=V^M(δ_A−δ_B)²−23060\barn(X_A−X_B)²
where δ_A and δ_B are the solubility parameters, and X_A and X_B are the electronegativities of the pure components, V^M is the molar volume of mixture, and \barn is the appropriate number of AB bond in the mixture.
The values of the interaction parameters thus calculated were compared with those determined experimentally in Fe-Cr-X, Fe-Ni-X, Fe-C-X and Fe-S-X systems, and reasonable agreements were obtained.

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An X-ray study of copper-aluminium and copper-nickel alloys was carried out. An asymmetrical line broadening was observed in a copper-aluminium alloy of high concentration of solute atoms but not in copper-nickel alloys. In the case of a copper-18.3% aluminium alloy the shift of the centre of gravity of the (111) diffraction line was estimated to be 0.05°, and interpreted to be due to the segregation of solute atoms and to deformation stacking faults. The effect of the segregation on the diffraction pattern was investigated using the equation by Willis, and as the result, in the case of copper-18.3% aluminium alloy the average scattering factors of the atoms in the normal and faulted layers were different from each other by about 6% after cold-working.

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Tracer diffusion mechanism in a polycrystalline medium with a plane source is discussed by assuming both the high diffusivity along the grain boundaries as compared with that inside the grains and the conservation of diffusant. The following theoretical results are obtained from the analytical solution of the problem. (1) In a small penetration region the grain boundaries act as sinks, i.e. a negative contribution to the amount of diffusant arises from the grain boundaries. (2) At a large penetration depth they act as sources, and the resultant positive contribution of grain boundary diffusion is such that the logarithm of the average concentration of diffusant from the boundary into the inside depends linearly on the 6/5 power of penetration depth. (3) Considering the grain size the present theory predicts the penetration curve in which both the lattice and the grain boundary diffusion play an important role. (4) The theory also finds the condition that the contribution from the lattice diffusion becomes dominant as compared with that from the grain boundary. A relation usable for the determination of the grain boundary diffusion coefficient from experimental data is given. These theoretical results are found in agree well with the experimental data. The limit for the validity of the present model is also discussed.

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The kinetics of dissolution of solid metals, Nickel, Copper and Silver in liquid Bismuth have been studied under static and isothermal conditions over a range of temperatures from 300° to 500°C. The measurements of the solution rate have been carried out by means of an electric resistivity method as well as chemical analysis. For these three systems, the solution rates have been found to obey the unimolecular reaction law expressed in the form of n=n{1−exp(−k·S⁄V·t)} and the solution rate constants are in nearly the same order of magnitude of 10⁻⁴ cm/sec. The activation energy of dissolution has been found to be about 2.2, 6.1 and 4.2 Kcal/mol for Ni-Bi, Cu-Bi and Ag-Bi systems, respectively. These experimental results have been discussed from the standpoint that the rate of dissolution is determined by the diffusion of solute atoms through the boundary layer of the solid-liquid metal interface.

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In view of the fact that three kinds of phase transformations, i.e. an eutectoid decomposition β→α+γ₂, an ordering transformation β→β₁, and a martensitic transformation β₁→β′ have been observed on isothermal holding and cooling at different rates from the β region in Cu-Al binary alloys, the author has tried to obtain the T/T/T diagrams in order to show the correlations between these three transformations. In the case of tempering the β′ martensite formed by water-quenching, the above three transformations have occurred in the reverse direction, and the T/T/T diagrams associated with the tempering process have also been determined.
Specific heat measurements and microscopic observations were carried out, and the X-ray diffraction pattern was used for phase identification during these heat-treatments.
As the result of the experiments, it was verified that the growth of the ordered domains of the Cu₃Al superlattice occurred below the critical temperature for ordering, Tc, when cooling from the β region, (therefore, the transformation β₁→α+γ₂ appeared instead of the eutectoid transformation β→α+γ₂,) and then the β′ martensite contained about 25% aluminium after air-cooling. On the other hand, in the case of tempering of quenched alloys the growth of the ordered domains occurred at temperatures above 400°C, and below 400°C the ordering did not occur, but the precipitation of α or γ₂ appeared preferentially.

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In many cases, it is desirable to use soft aluminium which recrystallizes at room temperature. It would be convenient as well as economical, if such aluminum could be made easily and cheaply.
This research was successful in lowering the recrystallization temperature to below room temperature by the addition of a small amount of calcium to aluminium of commercial purity with high temperature soaking, and by heat treatment for a long time at low temperature. It was proved that the matrix of aluminium containing impurities could be almost completely purified by changing the impurities to a harmless state by the addition of calcium and by heat treatment. Consequently, the aluminium alloy obtained, besides having the property of softening at room temperature, has the properties excelling in softness, workability, electric conductivity and corrosion resistance peculiar to high purity aluminium.
Further, it was found that impurities such as magnesium, manganese and copper can be more readily changed to a harmless state by the addition of small amounts of tin, nickel, etc., together with calcium, and general properties of the elements, which can purify the matrix of aluminium by the addition of them, were studied.

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Methods to produce Ti in massive lumps by the reaction between TiCl₄ and Mg were discussed theoretically and experimentally. These massive lumps were produced by a type of gaseous reaction by which the deposition of Ti was accompanied by the spontaneous ejection of the by-product MgCl₂ out of the reaction system during the course of the reaction. From preliminary experiments it was found that titanium subchlorides, TiCl₃ and TiCL₂, were produced if the reaction between TiCl₄ and Mg vapors took place in free space, but massive and compact Ti was deposited in a crystalline form with high efficiency when thle mixed vapors of TiCl₄ and Mg were caused to impinge and to react on the wall surfaces of Ti-ribbons stretched in the reaction chamber held at 900∼950°C.
The crystalline Ti deposited on the surfaces of the ribbons by these types of reactions was of a high purity and free from the MgCl₂ by products and excess Mg.

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Experiments on the production of Ti by the reaction between TiCl₄ and Mg vapors were carried out by using a large sized reaction furnace which consisted of a reaction chamber, a condensing tank for the condensation of the by-product MgCl₂ and excess Mg, and feeder tanks of TiCl₄ and Mg. The reaction chamber consists of a cylinder of 18-8 stainles steel, 30 cm in diameeter and 195 cm in length. Inside the reaction chamber were placed ribbons of Ti stretched net-wise in a mild steel frame. Vapors of TiCl₄ and Mg evaporated in their respective boilers were injected into the reaction chamber through jet nozzles at its top. The reaction mainly occurred on the surfaces of titanium ribbons very effectively and Ti was deposited on these surfaces and grew in crystalline lumps, while MgCl₂ vapor or excess Mg vapor was rapidly condensed in the waste tank. It was found that this method of producing Ti by the gaseous reaction was of a high efficiency in yields of TiCl₄ and Mg, in being accomplished in a single process, in requiring relatively a short reaction period and in producing large lumps of crystal Ti of a high purity free from MgCl₂ or Mg.
By reconstructing the lower part of the equipment the operation could be made continuous without cooling the reaction chamber and breaking its vacuum.

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The purity and the mechanical properties were examined experimentally on crystalline Ti produced by the gaseous reaction between TiCl₄ and Mg. Chemical analysis proved that the purity of the crystalline Ti was nearly as high as that of the iodide process Ti. When a slightly low grade of TiCl₄ or Mg was used as the raw materials too, high purity Ti was obtained due to the effects of distillation followed by the evaporation of TiCl₄ and Mg. The possibility of the admixture of Fe from the construction materials of the reaction was specially studied, and it was found that the admitxure of Fe was extremely reduced by using a graphite lining on the inner surfaces of the conducting pipes of TiCl₄ and by using Ti-coated frames and sleeves. Iron contamination can occur in the case of excess TiCl₄ which may be caused by the fluctuation in the flow rate of both vapors, therefore, when the control of the flow rate was kept precisely constant, the admixture of Fe could be kept below 0.01%.
The hardness of the crystalline Ti was between 82 to 100 in V.H.N. and 85 on an average. Tensile and Charpy impact tests were carried out and their results were 30 to 35 kg/mm² in tensile strength, 13 to 20 kg/mm² in yield strength, 84 to 82% in reduction of area and 58 to 60% in elongation. It was shown that crystalline Ti had excellent mechanical properties such as higher ductility in spite of slightly higher strength than the iodide process Ti. In the impact tests the specimens with a V notch and U notch were not broken in the low temperature range of liquid nitrogen, and the impact value of crystalline Ti was higher as the temperature was lowered.

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