Changes in electric resistance with varying temperatures were investigated on some thirty alloys of the α-solid solution of Ni-Cu-Zn system. An anomaly was observed at the temperatures between 300° and 450° with varying composition of alloys. This anomaly appears especially remarkable at compositions where Ni and Zn have same ratio; except in the copper-rich alloys.
Mean temperature coefficients of electric resistance between 20° and 100° of these ternary alloys with the same content of Cu generally increase with increasing content of Zn, except an irregularity at a probable composition haying same quantity of Ni and Zn, in which abnormally high temperature coefficient is observed.
As shown by the broken lines in the resistance _??_temperature curves of some cold-drawn wires of these alloys, we may anticipate the incomprehensible decrease of specific resistance, when these alloys were cold drawn, to be in close connection with the high temperature anomaly.
Besides these experiments, differential thermal analysis and differential dilatation measurements were carried out of an annealed alloy having remarkable high temperature anomaly. Heat evolution on the cooling curve and anomalous expansion on the heating curve, with Cu as neutral, were observed at the temperatures corresponding to the anomalous change in resistance. Further investigation on the cause of this anomaly is now going on.

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The immiscibility found in Cu-Fe alloys in the liquid state has been reinvestigated by the determination of the liquidus of these alloys as well as of the equilibrium of the liquid alloys at 1450° and 1540°, special attention being paid to the existence of a very small amount of carbon in the alloys. The results obtained are as follows; -
(1) On the liquidus curve of the pure Cu-Fe system no particular point can be found, and, consequently no monotectic reaction (as shown in Fig. 1) is likely to occur, (2) The existence of one per cent of Al, Ni, Pb, Sn or Zn in Cu-Fe alloys, consisting of 50 per cent. of Cu and 49 per cent. of Fe, does not cause the separation of the liquid into two layers. (3) In the C-Cu-Fe system two liquids co-exist in equilibrium at 1450° (Fig. 3) and 1540° (Fig. 4). Each heterogeneous zone lies very near the side (F'K' in Figs. 3 and 4) corresponding to the binary system consisting of Cu and Fe, but it does not cut that side, having a definite clearance (about 0.02_??_0.03 per cent. in carbon content) between the zone and the side. (4) Therefore it may be safely concluded that in the Cu-Fe alloys no separation of liquid into two phases take place, either when they are pure or have a carbon content of less than 0.02_??_0.03 per cent. in the range of temperatures up to 1540° and probably in a still higher range, while they separate into two liquid layers, when they contain more than the above percentage of carbon. The amount of carbon necessary to cause the separation varies as the content of iron in the alloy the larger the amount of iron in this the more carbon it must contain. (5) The temperature coefficient of the mutual solubility of the conjugates is found to be positive (Fig. 3 and 4), differing from the results found in the published reports (Fig. 1 and 2). It has also been explained how the temperature coefficient may falsely be taken as negative by a prcof of the fact that the higher the temperature at which the alloy is heated the greater the amount of carbon absorbed by it.

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Some investigators assumed the formation of BiSn₇, Bi₂Sn or BiSn₂ in the solid of the alloys of the Bi-Sn system. To verify the formation of the intermetallic compound and to clarify the nature of the change in the solid state of this alloy system, the present study was carried out by differential thermal analysis, volumetric dilatation method, electrical resistance method, X-ray analysis and microscopic examination. In the curves of differential thermal analysis no discontinuities were observed, while in electrical resistance and volumetric dilatation curves one or two were observed. From these results, the solubility curve of Bi in Sn-solid solution was determined (Fig. 10). X-ray analysis by Seemann-Bohlin's method denied the existence of any intermetallic compound in this system. So the discontinuity appeared at about 95° in the curves of electrical resistance and volumetric dilatation is due to the abrupt change in solubility of Bi in Sn-solid solution, and not to the formation of any compound.

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The constitution of Copper rich Cu-Al-Fe alloys containing up to 20 per cent. of aluminium and up to about 10 per cent. of iron was determined. A ternary phase, which is formed by a peritectic reaction, Liquid+Feγ_??_T, was found to exist, to which phase the authors named “T”.
The true natur of this ternary phase has not been thoroughly examined but its existence is ascertained by microscopical examination. The T phase has a large solubility of iron and aluminium, the homogeneous field extending from 20 to 27 per cent. of aluminium and from 25 to 45 per cent. of iron at room temperature.
The following invariant reactions were found to exist on solidification and in the solid state.
Liquid+T_??_β+Feγ 1048°
Liquid+Feγ_??_α+β 1046°
Liquid+β_??_γ₁+T 1015°
β+Feα_??_α+T 750°
α+Feγ_??_β+Fexχ about 950°
β_??_α+γ₂+T 560°
The latter ternary eutectoid reaction occurs at a temperature approximately 20° below that of the eutectoid temperature of copper-aluminium binary alloys.
The γ₂ phase of the Cu-Al system forms a range of solid solution, the maximum solubility of which with iron is about 2 per cent. at room temperature.

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The modulus of elasticity of various kinds of high yield point steels and carbon steels was measured with an ordinary triod valve magnetostriction oscillator, and it was found that the addition of small amounts of special elements to steels causes hardly any change in the modulus of elasticity.
The change in the modulus of elasticity of a carbon steel containing 0.1 percent. of carbon, due to cold working was also measured, the result of which shows that the cold working causes no appreciable change in the modulus of elasticity of the steel.
The modulus of elasticity of armco iron and of carbon steels containing 0.27, 0.46, 0.55 and 0.81 percent. of carbon was measured at elevated temperatures up to 600° the result of which is satisfied by the following formula
E_t2=E_t1e^{-a(t₂-t₁)}/_lm-t2 where t_m is the melting points of steelss.

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With some sixteen market wires of Ni-Cr and of Ni-Cr-Fe type, the effects of some factors on strength and electrical resistance were studied.
The strength and electrical resistance were found to vary a great extent both at room and elevated temperatures although difference in chemical composition was very slight. It is also shown that the tensile strength and the electrical resistances were influenced much more by working conditions and heat treatment than by chemical compositions. Surface defects, working ratio and crystal structures have great influence on the life of the wire.

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An X-ray investigation was carried out for the crystal structure of β₁-phase in the nickel-silicon system, and it was found that the β₁-phase, which is a face-centred cubic solid solution of the chemical formula Ni₃Si, has a superlattice, nickel atoms occupying centres of cube faces and silicon atoms cube corners.

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The Silicon-bronze, Cu-Zn-Si-alloy, which was developed by Dr. Tokiji Isikawa is comparatively light. strong and non-corrosible, and has many advantages as a substitute alloy for Tin-bronze. However, by annealing at 300_??_500°, it shows frailty, decreasing a shock value and elongation, increasing hardness, and yet almost does not change tensile strength. At the temperature of that range, the higher the temperature and the longer the times of annealing, the more brittle the alloy becomes. By the author's experimental results, when the alloy is annealed for a long time at the temperature of, 300_??_100°, it has become brittle. This is attributed to precipitation of γ phase in the grain boundary of a phase by decreasing solubility of Si in the α phase due to the addition of Zn. This precipitation could not be prevented by adding other. elements to the alloy. From the microscopic structures, the solubility of Si at 250° in Cu-Zn-alloys was found to be extremely smaller than that given in the former researches. Therefore it is concluded that the Silzin-bronze can be used only in the parts which require strength and non-corrosibility but not in the parts which are heated by steam, etc.

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