This paper treats the process of manufacturing special steels from electric pig iron and return scrap, without depending upon scrap bought from outside. It is, of course, desirable to make the pig iron with open hearth furnace and then refine it in the electric furnace, but this is impracticable to the factories that are equipped only with electric furnaces. So it must be of much necessity in our country to solve this important problem of raw material and to establish the so-called autonomous operation of manufacturing pig and steel (Sen-tetu Ikkwansagyô)

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The present study made some consideration on the results obtained at the Osaka Arsenal with regard to the melting operation of the high-grade steels using the acid electric furnace, following the former report. The authors equalized the temperature of the melt by full agitation, and determined it with an optical pyrometer. Taking it for the reaction temperature, they dealt with the carbon reaction, the silicon reaction and the manganese recation and the quantity of "sbnims." Thus they perceived that the CO gas always evaporates from the steel melt even at the static state without movement of the steel melt at the deoxidation period and the carbon reaction is always proceeding and that the flotation of the product of deoxidation depends on the adsorption of the gas evoloved as well as on the difference of densities of the steel melt. The flotation velocity was found to be fairly great. Moreover, the authors referred to the fact that the quality and purity of the acid furnace steel mostly depend on the oxidation rate {(FeO)×C}.

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It is commonly observed in the operation of electric furnaces, that the oxygen content of the steel melt is far more than the theoretical value for a certain carbon content.
In the present study, behavior of deoxydation due to the carbon in the steel melt was investigated, and the reason of retardation of deoxydation clarified, in view of obtaining reference data for improving the steel melting operation. The experiment was conducted with a Tammann furnace.
The sample was melted in a Tammann tube of magnesia. The author observed the behavior of deoxydation by varying the carbon and the oxygen content and reached the conclusion that the oxygen content agrees with the theoretical value when the carbon in the steel melt is small, while it becomes fairly more than the equilibrium-value when the carbon comes in excess of 0.2%. Besides, the author experimented the effect of varying temperatures and the effect of gas turbulance of the steel melt.

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Mit sternfdrmigen Probestücke u. a wurde der Einfluss der verschiedenen Elementen auf den Heissbruch des Stahlguss versucht. Die Ergbnisse sind folgendes:-
1. Die zur Heissbrüche in der nachste Beziehung stehenden Elemente sind S, Al, und Mn.
2. S und Al verstärken der Brach, die Wirkung der S ist erkennbar, obwohl sie sehr wenig ist.
3. Mn verhindert den Bruch.
4. Die Brüche stehen unter den bestimmten Beziehung zum Verhaltnis von Mn zu S.
Auch in dieser Erscheinungen befinden sich ciner gemeinsame, aber n cht quantitative Zusammen-hang und die Rotbruche. In dieser Folge vermutet ist, dass der hauptsachliche Grund des Vervorrufen der Heissbruch die dam Fe-S System angehörigen Verunreinigungenist, welche sich zwischen in die Korngrenze ausscheiden.

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1°-En vue de nous rendre compte de l'influence de surchauffage sur des aciers spécianx de construction, nous avons étudié, en surchauffaut des échantillons a de diverses témperatures 900° á 1350°C pendant 2 heures, lee changements de leurs fracteurs, des grosseurs réeles de grain austénitique, des propriétes statiques méchaniques, répétition de choc á la machine type Matumura, 2°- La question du temps de surchauff age est aussi étudiee. 3°-Le fait que la résistance de l'acier contre le sur- chauffage depend des additions déoxydante, a été constaté par l'auteur pour la prémiere fois. 4°-Enfin, un acier an Cr-Mo importe et un autre fabrique par la Cie Nippon Tolcusyukô ont été mis á l'étude, pour comparer leur résistance a le surchauffage.1°-En vue de nous rendre compte de l'influence de surchauffage sur des aciers spécianx de construction, nous avons étudié, en surchauffaut des échantillons a de diverses témperatures 900° á1350°C pendant 2 heures, lee changements de leurs fracteurs, des grosseurs réeles de grain austénitique, des propriétes statiques méchaniques, répétition de choc á la machine type Matumura, 2°- La question du temps de surchauff age est aussi étudiee. 3°-Le fait que la résistance de l'acier contre le sur-chauffage depend des additions déoxydante, a été constaté par l'auteur pour la prémiere fois. 4°-Enfin, un acier an Cr-Mo importe et un autre fabrique par la Cie Nippon TolcusyukÔ ont été mis á l'étude, pour comparer leur résistance a le surchauffage.

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The crushing test is defined by the Army and Navy Aeronautical Standard Specifications and the Japan Bearing Makers Association Standard Specification, as a strength specification for the use of high carbon and high-chromium bearing steel ( 501) for the outer and inner bearing races. The present test requires that a ring-form specimen of a certain dimension is crushed and the maximum crushing strength should be more than 4000 kg. However, as the method of calculating the stress is not indicated in the aforementioned specification, specimens outside the specified dimensions are not qualified to be used. Recently it becomes customary that ingots are first made into steel tubing, from which the outer and inner races for bear ing manufactured. Hence; it becomes necessary to know the required strength in case of the irre gular specimen outside the specified dimensions. Therefore, the author made a mechanical cons ideration on the crushing test from standpoint of the elasticity theory, and since a prospect of application of calculating formulae has been obtained from the elasticity theory, he derived the required equations which in turn proved to be practical by experiment.

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