In order to clarify the fundamental mechanisms of cermet sintering from the view points of surface- and interfacial tensions, the surface tensions of metals and alloys have been investigated experimentally as the first stage. The results obtained are as follows: The surface energy and the surface tension of a pure liquid are estimated with the bonding factor, B, or the surface tension factor, K, which are constants for liquids consisting of the same type of atomic bonding. The values are given by K_M\doteqdot0.16, K_I=0.07, B_V=0.5, B_M=0.18 and B_I=0.10. The suffix V, M and I represent molecular, metallic and ionic liquids respectively.
The surface tension of binary alloy changes in general smooth-concavely upwards with the concentration. If there are some high melting point compounds like silicide in the alloy system, the curve of surface tension vs concentration has a slight break. This fact and the distinct thermal coefficient of surface tension suggest that the dissociation of a compound is imperfect just above the melting point.
It was disclosed that carbon, Mo₂C and WC have little effects on the surface tension of iron, cobalt and nickel.
The assumption of adsorption of alloying elements is useful in understanding the surface tension of alloys.

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Experiments were made to study the resulting anistropy and texture of Al-Cu and Al-Si alloy sheets when the ingots are heat-treated. It was found that when the second phase of metallic compounds were dissolved by quenching and the ingot is in the state of supersaturated solid solution, the annealed sheet made from this ingot had large recrystallization grains and a recrystallization texture composed of type (100) [100] and 90° type ear by deep drawing. On the other hand, as far as the large amount of the second phase of metallic compounds exist in the ingot, the annealed sheet made from this ingot had very small recrystallization grains and a texture composed of type (123) [1\bar21] and 45° type ear. Moreover, when the ingot was artificially aged and fine metallic compounds precipitated, the annealed sheet had the eight ears combined 45° type and 90° type ear.
It may be pointed out that, in the process of recrystallization, the change of anisotropy and texture was restricted by the second phase of the metallic cmpounds, at the same time grain growth was also restricted.

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If the drawing direction of the wire is not aligned with the axis of the die-hole, the wire has to be continuously bent over the die-exit. The authors’ intention was to find out what influences the deflection (the angle α between the die-axis and the drawing direction) had on the properties of the wires drawn as described above. Copper and aluminium wires were used. It was determined that if α was more than 5°, hard copper wire decreased in strength, while aluminium wire became stronger. In all cases, the free looping diameter (the diameter of the wire-loop which results after the wire was drawn and thrown on the floor) sharply decreases if α was increased more than 5°, causing the wire to pile up very tightly on to the take-up drum.

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It is known that wire is influenced in strength if it is wound into a coil having a too small diameter. In the present report, not only the effects of coiling on the wire strength but also on the deformation of the coiled bundle are discussed. The materials used were hard copper and some of the copper alloy wires of high elasticities. The results reveal the following points:
(1) For hard copper wire, the coiling diameter should be more than 150 to 200 times the diameter of wire about 1 mm diameter, more than 110 to 150 times the diameter of 1 to 5 mm diameter wire.
(2) For avoid the twisting of wire bundles, the diameter of the take-up drum (spool) should be less than the free forming diameter of the coiled wire.

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Some of the fundamental problems concerning metallography encountered when copper-aluminium alloy systems are used for large casting such as marine propellers have been investigated. The microstructural analysis for “slow cooling brittleness or self-annealing” is obtained in copper-aluminium-nickel-iron quaternary alloys. In this paper the shift of the (α/α+δ) solubility limit curve, the coagulation of nickel and iron rich compound phase and the composition of κ phase in the alloys are discussed.
It is, also, shown that, in copper-aluminium-nickel-iron quaternary cast alloys, no precipitation of the eutectoid is observed even with an aluminium content of more than 9.4%, and stabilization is obtained at the (α+κ) phase with uniformly and finely dispersed precipitates.

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The microstructures of copper-aluminium-nickel-iron quaternary alloys, especially the cause of κ-phase precipitation, is greatly influenced by percentages of nickel and iron. And because these alloys are regarded as precipitation hardening alloys, the relationship between their type of precipitates and their mechanical properties is important. Therefore the relationship between microstructure and mechanical properties were investigated using quaternary alloys containing aluminium 9 to 10%, nickel 1 to 6% and iron 1 to 6%.
The effect of adding nickel and iron to copper-aluminium alloys is more remarkable in increasing the mechanical strength by κ-phase precipitation than in increasing the strength of the α matrix by dissolving into a solid solution. Nickel rich κ precipitates are a predominant factor for mechanical properties, and the effect of adding iron influences them by changing the type of the κ phase precipitates and the mean free path between particles.
A favorable mechanical properties were obtained when the Ni%+Fe% makes about 10% and the [Fe%]/[Ni%] ratio is about 1.1, and this is explained by the type of the κ phase precipitates and their distribution.

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The effect of adding additional elements such as manganese, silicon, zinc, tin, lead, beryllium, phosphorus, magnesium, cobalt, titanium, boron and chromium to the copper-aluminium-nickel-iron quaternary alloys on the microstructure and the mechanical properties have been investigated. From the results it was found that the effects of adding the above mentioned elements are classified into the following three groups from their behaviors:
(a) The elements that dissolve in the α solid solution and, when exceeding the solubility limit, cause the alloy to precipitate the (α+δ) eutectoid and increase the brittleness. Tin, beryllium, silicon, manganese and zinc are in this group, of which tin, beryllium and silicon produce a detrimental effect.
(b) The elements that produce hard spots or deteriorate the castability. Lead, chromium, boron, phosphorus and magnesium are in this group.
(c) No effect was observed when cobalt was added, which was considered to have an effect as a precipitation hardening constituent, perhaps owing to the small amount added.

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The fatigue fracture surfaces of some carbon steels were observed by electron microscope and their distinctive features are made clear, as follows. Experimental method: The so-called “Microfractography” with carbon replica by direct evaporation was applied. The carbon replica was stripped away from the specimen surface by electrolyting or by immersing in an alcoholic acid solution. Specimens: Specimens were made from steel bars with a carbon content of 0.3% or less and fractured with a rotating beam fatigue tester at stress levels ranging from 44.8 to 16.3 kg/mm². Results obtained: (1) The “river” or “tangue” pattern which are commonly on tensile or impact fracture surfaces were not observed on the fatigue surfaces. (2) Patterns observed on the fatigue surface can be classified into five types, which the author named “parallel”, “cliff”, “cleavage”, “caterpillar” and “spine” pattern. (3) The fine parallel patterns with a pitch of 100∼300 Å were found in specimens fractured at the stresses near the fatigue limit, while the coarse ones with intervals of 1000∼3000 Å were shown with higher stress level. (4) Every pitch of parallel pattarns corresponds nearly to the stress repeats of about ten cycles. (5) Both caterpillar and spine patterns were appeared on the specimens fractured at the repeats of the order of 10⁶, and were in a line perpendicular to the direction of crack propagation. (6) The “pit” of spine patterns and the “ridge” of caterpillar patterns were arranged in good order.
If we take a pit or ridge in a row of these patterns and denote x_k as the distance to the k th pit or ridge in the direction of broading intervals, then x_k=k²⁄C², where C is a constant.

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Studies on the constitution of silicate melts are very important not only in the fields of metallurgical processing or the glass industry, but also in dealing with the properties or constitution of liquids. For this reason a PbO-SiO₂ system was chosen as a model of silicate or slag because of its low melting point and glass forming properties.
As a result electrical conductivity measurements, it was found that the lead silicate melt had a positive temperature coefficient and ionic conductance like molten NaCl, which was verified by fused electrolysis. It should be noted that the curves showing the relation between electrical conductivity and composition have breaks at the compounds corresponding to 2PbO·SiO₂ and PbO·SiO₂. This irregularity was more clearly shown on the curves of activation energy of electrical conductance versus composition. This tendency was also observed in density and viscosity measurements.
The decomposition voltage of the melt was measured by using a Pt anode and molten Pb as a cathode. The electro-motive force of the cell −Pb/PbO(in silicate)/Pt:O₂+ was also studied. There was a general decrease of e.m.f. with increasing temperature and concentration of PbO. The activity of PbO in the melts obtained from e.m.f. was compared with values from Richardson’s experiments. On the decomposition voltage versus composition curves there are also two breaks at 2PbO·SiO₂ and PbO·SiO₂.
The differential thermal analysis with the aid of X-ray analysis was conducted in order to find out the mechanism of crystalization of lead silicate glass. The results indicate that even the stoichimetric compounds have different kinds of silicate anion, for example, 2PbO·SiO₂ has Si₂O_7⁶⁻ and others as well as SiO_4⁴⁻. A new crystal or compound was observed at the composition point corresponding to 3PbO·2SiO₂, but it was also found that this compound was decomposed to a mixture of 2PbO·SiO₂ and PbO·SiO₂ above 650°C. The results from the X-ray analysis of lead silicate glass, show that there are three similiar groups on the patterns, which coincide with the above mentioned discontinuity on the properties versus composition curves.

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Thermal contraction while cooling was prevented as a representation of a special thermal stress in the surface layer of steel induced by quenching. The effects of such thermal stress on retained austenite (γ_R) were as follows. (A) Experiments on high carbon alloy steels. (1) The tensile stress induced by preventing the thermal contraction increased linearly with decreasing temperature and indicated the maximum value at Ms temperature, that was about 10 kg/mm². (2) The amount of γ_R was markedly increased by preventing the thermal contraction. This is contrary to the expectation from the mechanism of martensite transformation which has been interpreted from the criterion of shearing stress. (3) The effective temperature range of stress on γ_R existed between 100∼150°C above Ms point and room temperature. (4) The rise of cooling speed at the range of above Ms temperature increased the amount of γ_R as the result of increment of induced tensile stress. (5) Below the Ms temperature, the rise of cooling speed decreased the amount of γ_R, similarly to free contraction cooling. Therefore it appears that there is no effect of stress on the thermal stabilization of austenite. (B) Stabilization of austenite by preventing thermal contraction was not observed in medium and low carbon alloy steels, and in low carbon alloy steel the amount of γ_R was decreased, contrary to the case with high carbon alloy steels.

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The dissociation pressure of gaseous vanadium in the reaction VC(s)=V(g)+C(graphite) has been determined in the range of 2346∼2545°K by means of Knudsen cell effusion method.
The pressure at the above temperature range is adequately expressed by logP_v(atm)=−30,400⁄T+7.50, from which, and coupling with the reported heat capacity data, the pertinent thermodynamic properties are calculated.

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In connection with the author’s 1st and 2nd report of “Quantitative Spectrochemical Analysis of Silicon and Vanadium in Titanium Tetrachloride”, the spectral line pairs for determination of magnesium, iron, manganese and silicon in titanium sponge were studied by 5×5 Graeco-Latin square experiments, bifactorial experiment and standard deviation, which was calculated from 50 repeated analysis.
The titanium sponge sample was dissolved without boiling in dilute hydrochloric acid (5 g Ti/50 cc HCl (1 : 1)) on a hot plate. All of the analytical conditions and procedures, except the sample preparation were identical to those described in the author’s 1st report. The variation coefficient and the limits of these line pairs for quantitative analysis are shown in Table 7.

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