Boron recently is known to have a pronounced influence on the hardness of the special steel. Hence a detailed study of this element in liquid iron containing oxygen is an important problem and of considerable interest. Therefore, the authors measured the equilibrium condition in the reaction between boron in liquid iron and the H₂-H₂O gas mixtures at 1600°C. The equation for the reaction was written as follows:
The equilibrium constant and free energy of the above reaction were, at 1600°C.
Next, the oxygen content of the molten iron at 1600°C was calculated from the following equation obtained by the author
Where x, y, were atomic fraction of oxygen and hydrogen in molten iron. Combining Eq. (1) with Eq. (2), the equilibrium relation between boron and oxygen in molten iron was obtained
The deoxidation product and the free energy as referred to the above reaction was expressed:
From these results, it was found that the present data differed greatly from the theoretical valuecalculated by R.W. Gurry, but are approximately in agreement with the experimental value obtained by Gerhard Derge.

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To study the behavior of sulphur in the furnace atmosphere the authors determind the quantity of SO₂ in the waste gas and calculated the amount of sulphur pickup from, or loss to, the furnace atmosphere. The amount of sulphur pickup during the charging period was the greatest as compared with that of melting period and appeared to be influenced widely by the sort and shape of the scrap being charged. Some theoretical investigation were made upon the equilibrium between sulphur in molten scrap and the furnace atmosphere using the known data.
During the melting and refining period the sulphur in the furnace atmosphere did not seem to have a direct influence upon the steel bath and also to be in equilibrium state with sulphur inslag.

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Up to this time, the potential measurment of molten slags was scarcely performed in comparison with that of the viscosity and electrical conductivity. In this paper, the author measured potentials in the binary systems K₂O, Na₂O, BaO, CaO-SiO₂ making use of the C-SiC electrode couple with the object of determination of activities of the constituents. As the result, it was clear that the systems K₂O, Na₂O-SiO₂; BaO-SiO₂; CaO-SiO₂ had some characteristics both in the magnitude and polarity of potential. This fact was due to the substantial difference in the construction of these systems.
Moreover, the next relations were proved to be established between the activities a_SiO2 a_CaO of these slags and potentials,
where E, E': measured e.m.f., E_o, E_o': standard e.m.f., m, m': molar numbers of constituents, n, n': numbers of electron, R: gas constant, T: absolute temperature, F: Faraday's constant.
The author suggested that a_sio2 or a_CaO could be derived from the measurement of the decomposition voltages and this potential values.

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Because of small resources of tungsten, chromium and vanadium, which are the most important elements in high speed steel, it is an urgent problem in Japan to extract these elements from oxidizing slag, hammer scale or grinding wastes in steel works.
The auther attempted the extraction of these elements by the following methods in Heroult furnace and obtained a good result: i.e the extraction rates of tungsten, chromium and vanadium were at least 90%, 80% and 20% respectively.
1) Addition of the oxidizing slag to the specially prepared carbide slag.
2) Direct reduction of scales and grinding wastes in coaks powder and ferro-silicon.
The auther also calculated the equilibrium condition between oxides of these elements and carbon and proved that the best working temperature range for extraction of the tungsten and chromium from 1600°C to 1650°C, but extraction of the vanadium wus almost impossible at that temperature range.

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Effects of boron addition on grain sizes, critical temperatures, Jominy hardenabilities and isothermal transformation diagrams were studied with several kinds of constructional alloy steels prepared from commercial and experimental heats. The results obtained were summarized as follows.
1. The perfect deoxidation and nitrogen fixing of the heat by proper addition of Al+Ti, prior to the boron addition was proved to be effective to increase hardenability and also to avoid grain coarsing tendency of boron steel.
2. The intensity of the boron effect on hardenability was apparently larger in Mo-containing steels especially-in complex low alloy steels than in simple alloy steels.
3. Boron appeared to retard nucleation of ferrite both in continuous cooling and isothermal transformations, accordingly it seemed to retard the begining of proeutectoid ferrite, intermeadiate and pearite transformations in hypoeutectoid steel.
Decreasing effect of boron in higher carbon steels and practically no effect at eutectoid and hypereutectoid steels was considered to prove that boron only delayed the nucleation of ferrite but it did not affect on the nucleation of carbide.
4. A "boron constituent" at the austenitic grain boundary was observed, after the grain coarsing by heating at 1200°C followed by slow cooling.

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The mechanical properties of heat-resisting steel depend not only upon the chemical composition but greatly upon the heat treatment. The authors studied the effect of carbon, silicon, manganese and nickel contents on the aging of Ni-Cr austenitic heat-resisting steel containing 15% Ni and 20% Cr.
The authors first examined change of their hardness due to various heat treatments of each sample: i, e solid solution treatment and aging, and then observed the microstructure.
As the results of these experiments, they gave most moderate composition and heat treatment for Ni-Cr austenitic heat-resisting steel, concluding that (1) C0.3-0.4%, Si1.5-2.5%, Mn Ni15-20% were conforming to Cr20%. (2) The solution treatment was made at 1200-1250°C, and the aging temperature was 700-750°C, the aging time being 6-12 hours.

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The effect of austempering on the subsequent tempering behavior in a high speed steel containing 0.65% C, 15.92% W, 4.30% Cr, 0.76% V and 2.64% Co was investigated by means of the microscopic examination and the hardness test.
In the austempering, each specimen was quenched into a hot salt bath of a given temperature between 200°C and 600°C from the austenitizing temperature of 1300°C or 1330°C, soaked there for a given period less than 5 hours, and then cooled in atmosphere.
The results obtained were summarized as follows:
(1) The isothermal transformation of austenite did not accur in any austempering except at the temperature range between about 250°C and 350°C, where acicular lower-bainite was formed.
(2) In general, those following austempering had different influence on the change in hardness by the subsequent tempering from the normal oil-quenching;
(i) After austempering at 600°C, the initial softening on tempering at 300°-400°C scarcely occured, while it was a common phenomenon after oil-quenching.
(ii) After austempering at the bainiterang, which decreased the hardness at room temperature, a large amount of secondary hardening took place and consequently the maximum tempering hardness became the same with that after oil-quenching.

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It had been known for many years in malleable foundries that small amounts of chromium having the retarding effect on the graphitization of ordinary black heart malleable iron both in the first and second stage annealing, especially on the latter. No research, however, with effective results to neutralize the retarding effect of chromium on annealing rate had been done. In view of the fact that manganese having strong affinity with sulphur neutralized the strong retarding effect of sulphur by forming manganese sulphide, if there were some alloying elements having strong affinity with chromium were investigated. As no detailed publication on the affinity among elements had been described, however, the auhors' researches were directed towards to investigate effects of 21 alloying elements on graphitization of the white iron containing 0.156% of chromium.
Results obtained were summarized as follows:
1) The ferrite matrix which was characteristic of malleable iron did not appear in the most specimens without containing boron, aluminium, silicon and 0.2% titanium and copper above 2.0 per cent. 2) Better results were obtained by adding aluminium, silicon, titanium, copper, boron and zirconium which had been known as strong deoxydizers. It had not yet been made clear however, if there were close relation between the better effect of above mentioned alloying elements in graphitization and the retarding effect of chromium.
It was concluded that there was no strong graphitizer by which was neutratized the retarding effect of chromium as in order of 0.156% per cent content in the present research field.

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Studies & utilizations of sand iron has been developing in Japan. There are many sand iron. sources in Hokkaido. Therefore Muroran Iron Works has been using a larger quantity of sand iron as compared with other works. The authors wanted to analyse the sand iron and the sinter mixed with sand iron more rapidly and more accurately. But these samples were difficult to dissolve, so the alkali melting or hydrofluoric acid melting method was applyed in which the platinum or china vessel was required for these analysis.
But it was necessary to save such long time required and to save special vessels, and many samples could not be treated in a time for such analysis. The authors found the following method by addition of H₃PO₄, to the samples.
1. Fixing the quantity of T.Fe
Add H₃PO₄ to the sample and add a small quantity of HCl to oxidize it to make FeCl₃ after dissolution of the sample and then the quantity of Fe was fixed by the normal method.
2. Fixing the quantity of TiO₂
Add H₂SO₄ & H₃PO₄ to this sample and give to colour with H₂O₂ after dissolution of the sample and then compare it with the standard.
3. Fixing the quantity of As
After treating the sample with (1/3H₂SO₄+2/3HCl), add H₃PO₄ to it and dissolved it, and then add the SnCl₂ solution. Thus determine the metallic As and then fix the quantity of the metal.
In this paper the simple analytical method was reported.

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In Hoshizaki plant of Daido Steel Works, Ltd. making special steels, a small quantity production with a variety of steel types is being performed and there are a number of problems unsolved technically with regard to the relation of the quality characteristics and the factors, that may be dealt with by application of methods of stocaistics.
The variance-analysis of stocaistics was herein applied to part of the experimental results of the sulphur determination in a certain kind of steel. There are so many methods in chemical analysis of the sulphur. Experiments were made, however, because there had occurred some doubts abouts the data of the sulphur anaylsis of the steel concerned.
In the field of these experiments, the combustion temperature and the specimen forms gave significant variations to the value of analysis. Since the rapid analysis was considered generally to give a value less than the data by gravimetric method, the form of the specimen should be better of the lighter section and the combustion temperature should be preferably the more elevated.

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(1) For the sake of contributions to better understanding of the chemical reactions in which a molten furnace-slag takes part among the steelmaking practices, and control of the practical operations, efforts should be given again to make up the model of a molten slag as faithful as possible to his microscopic constructions.
(2) For this it was desirable to utilize the excellent idea found at the time when a number of approximate treatment which had ever been proposed was examined thoroughly.
(3) The concrete method calculating the slag basicity was extensively explained which related intimately to the steelmaking operations as an indicator of "slag control" and the active concentrations of main slag components, especially of (FeO) and more accurately activity of those. Moreover it was emphasized how important role was being played by an activity of the several components of both phases in case of the slag-metal interface reactions.
(4) As one trial a characteristic value "B_r" of a molten slag was proposed in place of the customary slag basicity, for instance ΣCaO/ΣSiO₂, together with investigation of some properties.
Successively the usefulness of the correlation analysis was shown with a number of practical and experimental data so as to anticipate, for example, the deoxidation, desulphurization and dephosphorization power of a molten slag combining with "B_r" (%FeO), (%C) or the temperature reported.

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