The absorption spectra of Ru(III) and Rh(III) in the fused LiCl-KCl eutectic were measured in the spectrum range from 43000 to 10000 cm⁻¹ at various temperatures between 400° and 600°C.
At 400°C, the peak positions of Ru(III) were found at 28700, 24700, and 18300 cm⁻¹, and the Rh(III) at 38800, 23500, and 18400 cm⁻¹. In the d-d transition bands, 18300 cm⁻¹ in Ru(III) and 23500 and 18400 cm⁻¹ in Rh(III), both bathochromic and hyperchromic effects were observed to increase with increase in temperature. From the comparison of the above results and the absorption spectra of Ru(III) and Rh(III) in an aqueous solution of high chloride concentration, the species of Ru(III) and Rh(III) present in this solvent are assumed to be [RuCl₆]³⁻ and [RhCl₆]³⁻.

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Wear experiments of flaky graphite cast iron against 0.6%C carbon steel, stainless steels (SUS 24, SUS 27) and Ni-Cu alloy (Constantan) were carried out under metal-to-metal, unlubricated conditions. The extremely hardened layers were developed on the sliding surfaces of cast iron at sliding speeds faster than 2 m/sec. The hardened layers were examined by X-ray diffraction and the relation between formation of the hardened layers and wear of cast iron was discussed.
The results are summerized as follows:
(1) The hardened layers are generated at speeds above the second oxidative wear speed and in mild wear condition, and are not found in severe wear process even at high sliding speeds.
(2) The hardened layers are due to rapid solidification of melting regions on real contacting asperities. They may be worked severely during and after solidification and tempered by frictional heating.
(3) As the sliding speed is increased at a constant contact pressure, the hardness of the hardened layers decreases and wear varies complicatedly with the minimum wear rate at about 4 m/sec. Softening of the hardened layers with increasing sliding speed may be due to the rise in quenching and tempering temperatures.
(4) As the contact pressure is increased at a constant sliding speed, both the wear rate and the hardness of the hardened layers increase exponentially and lineally. The effects of work hardening due to the increase in contact pressure and the shortening of the remaining time of the hardened layers on the sliding surface due to the large wear rate may be stronger than due to the temperature rise with increasing contact pressure.
(5) Accordingly, the hardness of the hardened layers is under the influence of the sliding and wear conditions. There is no definite relation between the hardened layers and the wear rate.

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The solid solutions of the Cd₃P₂-Zn₃P₂ system have been prepared by either a direct melting method or a sintering method, and their physical, electrical and thermal properties have been measured. The main results are as follows:
The Cd₃P₂-Zn₃P₂ system is pseudo-binary, and a continuous series of solid solutions having lattices of tetragonal symmetry is formed throughout the whole range of composition. However, in the temperature range above the solidus line of the system, the phase diagram would be rather complicated, probably being influenced by the intricate phases at high temperatures of the Cd₃P₂ composition. The Cd₃P₂-Zn₃P₂ system has two solid phase transformations. The one is a kind of polymorphic transformations which occurs over the whole composition range above 730°C, and the other is probably a second order transformation which exists in the composition range from about 10 to 50 mol%Cd₃P₂ below about 500°C. The transition of the type of conductivity in the system takes place at a composition between 40 and 50 mol%Cd₃P₂. All the solid solutions show rather low total thermal conductivities of 0.012∼0.024 W/cm·deg at room temperature.

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The determination of various alloying elements in Ti-base alloys by X-ray fluorescence spectroscopy was investigated in order to develop a rapid quantitative method for the analysis of a large number of samples.
Measurement are made with Fluroprint Mk-II spectrometer, using W-tube rating at 50 kV-20 mA.
The drilled sample is converted to an oxide directly with the ignition in the electric furnace or by chemical treatment. Oxide powder ground under 100 mesh (1 g) is fused with Na₂B₄O₇ (15 g) in Pt crucible to a complete molten glass, which is poured into a graphite mold preheated at 350°∼400°C to form a glass bead. The glass bead has satisfactory homogeneity for X-ray fluorescence analysis, which was proved by the segregation tests of chemical analysis and autoradiography.
Optimum operating conditions for determing Al, Co, Cr, Cu, Fe, Mn, Mo, Nb, Pd, Sn, Ta, V, W and Zr in the concentration from 0.1 to 15% are given. The sensitivity is within 0.1% for heavy elements on the uses of K X-ray spectral lines as the detecting source. The precision is within 5% of the amount present. Results agree well with those obtained by the routine method for chemical analysis and the calibration curves prepared from synthetic standards having a different history, are linear over most of all the concentration range of the analytical elements in various samples.
This study suggests that the method could be applicable easily to the analysis of the other kinds of alloy after some modifications.

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Hydrogen reduction of NiO under high pressure up to 31 atm was studied at 200°C, 220°C and 240°C. Oxide powder of less than 200 mesh was reduced in a high-pressure type electric furnace, and the reduction ratio was calculated from the weight change of the sample before and after reduction.
Plots of reduction ratio versus time gave sigmoid curves characteristic of the auto-catalytic reduction of NiO and the rate equation 1−(1−R)^1⁄3=Kt, which is used for the reaction controlled by the interface area, could be applied in the main reduction period from about 30 to 80%. With rising hydrogen pressure, the reduction rate increased remarkably, and at about 10 atm it showed 3 times larger than that of one atmosphere at each temperature. Moreover, the higher the temperature, the more remarkable became the actual effect of pressure. However, a further rise of pressure did not effect significantly. The relation between the apparent reduction rate K (min⁻¹) and hydrogen pressure was represented by Langmuir’s type formula K=aP_H2⁄1+bP_H2. Furthermore, the experimental results were discussed from a kinetic point of view.

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Interdiffusion in γ solid solutions of the Fe-Mn system, was studied in the temperature range between 930° and 1250°C, using the diffusion couples of pure Fe and the alloy.
Interdiffusion coefficients \ ildeD were determined by the Matano analysis. At 930°C, because of the marked grain boundary diffusion, \ ildeD was impossible to be evaluated. And at 1010°C, it was noted that the dependence of \ ildeD on concentration differed from that in the higher temperature range, and in plotting \ ildeD against 1⁄T, \ ildeD deviated from the linearity in the same temperature range.
From the Arrhenius relationship, the activation energies \ ildeQ and the frequency factors \ ildeD₀ for the interdiffusion in 5∼55%Mn alloys were calculated and it was shown that the results can be expressed as follows:
(This article is not displayable. Please see full text pdf.)
The shifts of the Kirkendall marker showed that Mn atoms diffuse faster than Fe atoms in the vicinity of the 38%Mn composition.

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The strength of sintered WC-10%Co alloys containing 0∼80% additive carbides such as tantalum, niobium and titanium carbides, etc., has been studied in relation to their microstructures.
The results obtained were as follows: (1) The strength vs. carbide content curves for various alloy systems were divided into three or four regions showing each characteristic structure according to the carbide contents. (2) However, it was found that the shape or the strength level of the curve varied markedly even in the same alloy system, with varying sintered particle size of WC and additive carbides (s.s. phase), or with varying dimension as well as grain size of the carbide-agglomerate formed when the alloys contained a large amount of carbide. (3) The effects of additive carbides on the strength of the alloys were understood from the following three factors characteristic of carbides: the effectiveness on the inhibitation of recrystallization of WC, the inherent property such as the strength or interfacial energy, and the dimensional factor of sintered additive carbides. The third factor was naturally related to the tendency of the grain growth or agglomeration, and to the surface to surface spacing of carbides, i.e., the particle size and the volume fraction before sintering. (4) As a results, a certain WC/TiC/TaC triple carbide was shown to be the most favorable as the additive carbide, because the strength decrease in WC-Co alloy due to the addition of the carbide was minimized compared with the other carbides.

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The phenomenon and mechanism of high-temperature embrittleness in Cu-Cr alloy were studied. Commercially available Cu-1.0%Cr alloys solution annealed, quenched, or subsequently cold-worked were aged at various temperatures up to 700°C. These specimens were tensile-tested in the temperature range as above. As for the mechanism, the microstructures of tensile-strained or fractured specimens were mainly examined by means of optical and electron microscopy, EPMA, etc.
The results obtained were as follows: (1) The alloy except in the over-aged state always showed marked embrittleness at about 500°C. (2) Although the phenomenon was associated with intergranular fracture, any abnormality at or near grain boundaries was never detected. (3) It was suggested from the microstructural studies that the embrittleness was due to (i) the high stress concentration at the grain boundaries caused by blocking of the slip bands and (ii) the decrease in strength of the grain boundaries with rising temperatures.

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In diesem Aufsatz wurde die Änderung der mechanischen Eigenschaften des Stahldrahtes durch das Durchlaufbiegeverarbeiten untersucht und daraus liessen sich die folgende Schlüsse ziehen.
(1) Beim Durchlaufbiegeverarbeiten des patentierten Stahldrahtes findet eine Zunahme der Zugfestigkeit und Streckgrenze statt, während gleichzeitig die Dehnung erniedrigt wird. Beim gezogenen Stahldraht haben diese Eigenschaften bei starkem Biegen die gleiche Neigung wie beim patentierten Stahldraht, während bei leichtem Biegendagegen die Zugfestigkeit und Streckgrenze abnehmen und die Dehnung zunimmt.
(2) Beim Durchlaufverarbeiten des Stahldrahtes mit Gegenzug werden die Zugfestigkeit und in besonders ausprägtem Masse Streckgrenze grösser und wird die Dehnung niedriger als beim ohne Gegenzug.
(3) Der durchlaufbiegeverarbeitete Stahldraht ist bei den geringen Abnahmen des Drahtdurchmessers niedriger in Zugfestigkeit und Streckgrenze und grösser in Dehnung, bei den stärkeren Abnahmen dagegen höher in Zugfestigkeit und Streckgrenze und geringer in Dehnung als der auf Ziehstein gezogene Stahldraht.

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In order to investigate the martensitic transformation in Fe-Cr-Ni stainless steel, the Ni equivalent has been introduced thermodynamically as a universal quantity which indicates stability of austenite with regard to chemical composition. The relation between the Ni equivalent and the amount of strain-induced martensite or athermal martensite has been studied by means of saturation flux density measurement. Furthermore, the mechanism of the formation of strain-induced martensite has been considered thermodynamically.
The results obtained are summarized as follows:
(1) The Ni equivalent, (Ni), in Fe-Cr-Ni stainless steel is expressed by
\phantom(1)(Ni)=Ni+0.65Cr+0.98Mo+1.05Mn+0.35Si+12.6C
\ oindentwhere Ni, Cr, etc. represent weight % of these elements in the stainless steel considered.
(2) The relation between the Ni equivalent and the amount of strain-induced or athermal martensite has been obtained.
(3) About 75% cold rolling of Fe-Cr-Ni stainless steel has the same effect on martensitic transformation as decreasing the Ni content by 3∼5%. In this case, the difference in the free energy at room temperature between the ferrite phase and the austenite phase increases by about 113∼188 cal/mol.
(4) The deduced value of the work done by transformation strain induced by the applied stress due to cold rolling is about 120∼126 cal/mol or about 192 cal/mol by compressive or tensile stress, respectively. These values agree very well with the above mentioned change of the free energy difference calculated from the variation in Ni equivalent. Therefore, under applied stress, the stored free energy required for martensitic transformation can be lowered by this work value, 120∼192 cal/mol.

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The object of this work was to investigate the relation between mechanical properties and martensitic transformation or chemical composition of Fe-Cr-Ni stainless steel. First, the relations between mechanical properties (tensile strength, Young’s modulus, Federungs Grenze) and structures of specimens were investigated in order to clarify the influence of martensite on these properties. Second, the influence of the Ni equivalent (which is a quantity determined by the chemical composition and has an immediate effect on the martensitic transformation) on the mechanical properties was examined. The details of the Ni equivalent were reported in the previous paper.
The results obtained are summarized as follows:
(1) In the chemical composition range between about 20.7 and about 25%Ni equivalents, the variation in mechanical properties of the cold rolled specimens caused by composition changes was remarkable because of the difference in the amount of generated martensite.
(2) The highest strength of the cold rolled specimens were obtained for the composition of about 20.7%Ni equivalent where the amount of strain-induced martensite was maximum. For the composition less than the above-mentioned Ni equivalent, the tensile strength became somewhat lower. However, for the composition higher than the above, the strength remarkably decreased, and for that above 25%Ni equivalent, it stayed constant at alow value.
(3) Strain-induced martensite had the highest strength in the cold rolled specimens, athermal martensite had a rather lower, and austenite structure had the lowest. The strength of each structure was estimated.
(4) The tensile strength of the solution-heat treated specimens had almost the same features as the cold-rolled specimens. However, no decrease of the strength was observed even if the Ni equivalent was lower than 20.7%, and good elongation was obtained for the composition of high Ni equivalent where the austenite structure is stable.
(5) The influence of the carbon content on Federungs Grenze of the 75% cold rolled specimens was not appreciable for the composition of more than 0.04% carbon. On the contrary, for the composition of less than 0.005% carbon, a remarkable decrease in Federungs Grenze was observed.

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The drawability of 18Cr stainless steel sheets is strongly affected by the crystallographic orientation and not by the grain size. The drawability of 18Cr stainless steel sheets produced by a single cold rolling and annealing process is very poor, because a considerable amount of the {100} component parallel to the sheet plane, which is mainly composed of {100}⟨011⟩ inherited from the hot rolled condition, is retained and the increase of the {111} component can hardly be anticipated in the process.
In general, 18Cr stainless steel thin sheets are produced by a double cold rolling and annealing process. It is well known that the drawability of mild steel sheets of greatly improved drawability can be processed in the “double” process. So it has been tried to improve the drawability of 18Cr stainless steel sheets by the application of the “double” process.
Consequently, it is found that the drawability of 18Cr stainless steel sheets is greatly improved by a proper combination of cold rolling reduction in each stage.

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There is a large amount of {100}⟨011⟩ component in hot rolled 18Cr stainless steel sheets. Therefore, the drawability of commercial 18Cr stainless steel sheets is poor and the r value is small. In order to obtain 18Cr stainless steel sheets with excellent drawability, it is necessary to establish such a process as to minimize the {100}⟨011⟩ component.
For this purpose, two processing methods are attempted. One of them has a pre-treatment process which consists of reheating the hot rolled sheet to the α+r region and water quenching.
The drawability can be much improved by adopting this pre-treatment process. The sheet with the best drawability processed by this method has six ears after drawing. So it is considered that the preferred orientation of these sheets is {111}⟨112⟩.
The other attempt is to find the most appropriate condition of hot rolling.
Furthermore, it is found that the role of the “double process” is more dominant than that of above two procedures.

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An ultra high temperature hardness tester which is capable of reading the hot hardness value up to 1700°C was devised recently. The hardness tester has an extra ordinary construction to protect the influence of high light scattering from the ultra highly heated specimen, and the impression image is obtained by reflected electrons from a scanning type electron microscope. The specimen surface image, therefore, is clearly visible over the whole temperature range. The specimen temperature is elevated by electron bombardment up to 2000°C and the temperature is calibrated by observing surface images of various pure metals in the melting and solidifying states. For example, 3.8 mmg of pure platinum (meiting pt. 1770°C) image is clearly observed during the melting procedure. An indenter is located inside of a heating furnace, so the both specimen and indenter tip are heated to the desired temperature. The indenter tip temperature, therefore, is elevated sufficiently before applying a dead weight to a specimen. In a general relation between the hot hardness value and temperature for pure iron and pure tantalum, the inflection points are at lower temperatures rather than those in the previous data. Most of the hot hardness values for pure iron are also slightly lowered in high temperature range over the inflection point. The creep effect on the hot hardness is obviously recognized at the temperatures over the inflection point, but this effect may not extend over the temperatures below 500°C for pure iron. And a higher hot hardness value is always observed under a lower test load except over 800°C. On the other hand, the all-sapphire indenter gives a higher value of hot hardness than the sapphire tipped indenter. This result may also be considered the difference of thermal conductivity from the all-sapphire and sapphire tipped indenters. Hot hardness measurements have long been done with the diamond tipped indenter which gives a much higher value of hardness. Diamond has a higher thermal conductivity than sapphire and is apt to react with various metallic specimens at higher temperature. Moreover, the use of the higher test load is not suitable for an accurate measurement of hot hardness because of the possibility of thermal drift between a specimen and the indenter tip and the promotion of the creep effect. Therefore, it seems more desirable to conduct the hot hardness measurement under a constant test load as low as 50 g either with the all-sapphire indenter.

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In order to prevent the localized attack on stainless steels, cathodic protection tests were carried out by the potentiostatic and galvanostatic methods in the room and sea environments. The results obtained are summarized as follows:
(1) When the cathodic protection is not carried out, localized attacks are caused by the differential aeration cell under the attachment of barnacles on the high grade stainless steel (22Cr-25Ni-5Mo). On the other hand, the attack is prevented by the cathodic protection for the low grade stainless steel (18Cr-8Ni).
(2) On the low grade stainless steel, localized attacks occur at the cathodic protection potential of −0.05 (natural electrode potential) to −0.5 V, but no attacks occur at the potential of −0.8 to −1.0 V.
(3) On weldments, localized attacks easily occur resulting from the preferential attack of ferrite at bonds. But the attack is prevented perfectly by the cathodic protection set at −0.8 V.
(4) Localized attacks are considerably accelerated by the preferential attack along grain boundaries on which Cr carbides are precipitated. But on such heat-treated stainless steels, the attack is prevented by the cathodic protection set at −0.8 V.
(5) The condition to prevent the localized attack on stainless steels is to hold the protection potential at the potential of −0.6 to −0.9 V or to hold the current density of 7 to 12 μA/cm².

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In our previous paper, the dissolution of solid copper into liquid tin and the influences of the additional elements to liquid tin were reported as a fundamental research of soldering. The purpose of this study is to make clear the growth process of an alloy layer formed between solid copper and liquid tin which has influence upon the mechanical properties of solidered joints. A static study has been made on the process of the growth of alloy layer under the condition with or without dissolution of solid copper during the reaction. The results obtained from the experiments made at different temperature in the range 320°∼580°C are summerized as follows:
(1) A formula W=b×t^a between thickness of alloy layer W and reaction time t was derived for the growth of alloy layer and the values of a were 0.38 for η phase and 0.53 for ε, δ, and γ phases, under the condition without dissolution of solid copper in copper saturated liquid tin alloys.
(2) The temperature dependence of b in the formula W=b×t^a was found to obey an activation process of the Arrhenius type.
(3) Under the condition with dissolution of solid copper, the value of a was 1.0, that is, the thickness of alloy layer increased in proportion to the reaction time.
(4) It has been made clear by microscopic observation that under the condition with dissolution, the alloy layer grew in intensive competition with the dissolution of solid copper.

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The surface tension, density and viscosity coefficient of PbO-SiO₂-Li₂O ternary melts have been measured in the temperature range 800° to 1200°C by the use of the dipping cylinder method, the Archimedean method and the counter-sphere method, respectively.
In the (PbO·SiO₂)-Li₂O pseudo binary system, the surface tension decreases with the addition of Li₂O. The characteristic phenomenon may be explained in terms of the production of a homopolar Pb-O bond in the melt with the addition of Li₂O.
The negative deviation of molar volume from the additivity and the decrement of viscosity coefficient with the addition of Li₂O indicate the bond breaking of SiO₂ network and the production of descrete anions.
Logarithm of viscosity, logη, shows a linear relation with 1⁄T² rather than with 1⁄T. The apparent activation energy of viscous flow decreases with increasing Li₂O content for the (PbO·SiO₂)-Li₂O and (PbO·SiO₂)-(Li₂O·SiO₂) systems.

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Magnetic properties of Ag-Mn-Sb alloys containing 2.49∼69.95%Mn and 4.58∼70.02%Sb have been measured. It has been found that the alloys consisting of about 13∼34%Mn, 23∼42%Sb and 26∼64%Ag show high coercive forces when tempered at 50°∼200°C after chill casting and the alloy consisting of 24.08%Mn, 35.10%Sb and the rest Ag exhibits the highest coercive force, _IH_C, of 1600 Oe and a residual intensity of magnetization, I_r, of 27 e.m.u. Further it has been determined by means of electron microscopic observation and X-ray analysis that these alloys of high coercivity consist of many fine particles of the ferrimagnetic compound Mn₂Sb dispersed in the matrix of the nonmagnetic α_Ag phase. The high coercivity of these alloys is probably caused by the crystal- and shape-magnetic anisotropy energies in those fine particles of a single magnetic domain.

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Please see pdf. Wrong:[in Japanese], [in Japanese] Right:[in Japanese], [in Japanese]

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A guide for the heat treatment of Si-Fe alloys containing up to 3.9%Si being used as various core materials was presented from the practical point of view. It was found that magnetic properties in Si-Fe alloys containing more than about 2.5%Si are considerably affected by the cooling rate during the heat treatment and improved by a rapid cooling. The rapid cooling effect expressed as the percentage increase of the magnetic quantities such as maximum permeability or B_0.5 at intermediate fields depends on the purity of specimens and the operating temperature. The effective cooling rate is below 40 min which is the time taken to cool from 800°C to 200°C. The greater the cooling velocity, the more excellent magnetic properties are obtainable when other conditions than above-mentioned are appropriate, except that the heat stress is generated in the specimens by quenching. As the method, air-quenching and oil-quenching were undertaken in this work. The excellent properties thus obtained were not so changed by aging treatment at 100°C for a long time, but were notably deteriorated at 150°C.
From the above considerations and the results obtained by micrographic observation, it seems reasonable to interpret that the rapid cooling effect is due to the interstitial impurities such as C and N which are dissolved at higher temperatures and frozen at room temperature by rapid cooling from the high temperature; if the specimens are slowly cooled or aged, these impurity elements probably precipitate as non-magnetic inclusions, and consequently are always deterimental to this effect.

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The work of adhesion has been determined by the measurement of the contact angle between liquid metals such as Ag, Au, Cu, Fe-C and Sn and metallic oxides as MgO, SiO₂ and Al₂O₃. Contact angles are very sensitive to the experimental conditions and so different data have been reported by previous investigators. To obtain some information on the interface between liquid metal and oxides, a series of test should be carried out under the same condition.
In this paper, the work of adhesion is estimated roughly according to Pask’s model and compared with the experimental values. The results obtained are summarized as follows:
(1) The dispersion force is a major part of the interface force between liquid metal and oxide.
(2) The work of adhesion is related to the free energy change with the oxidation of liquid metal.
(3) Contact angles are very sensitive to the atmospere which has the effect on the interfacial structure of materials.

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