As a supplement for the former experiment on the influence of added salt on the passivity of chromium steel in sulphuric and hydrochloric acid solutions, the writer carried out the similar experiment for nitric acid solution.
It was ascertained that 10-14 percent chromium steels can be passivified in dilute (say, 5% HNO₃) nitric acid solutions containing metallic cation of higher valency, for example, Cu⁺⁺, Fe⁺⁺⁺, but not passivified in solutions containing metallic cation of lower valency or that of non-variable. These relations are quite similar to that in the case of sulphuric and hydrochloric acid solutions.
Next, 10-12 percent chromium steels are spontaneously passivified in dilute nitric acid solution containing no metallic cation of higher valency, or initial rate of attack of the acid gradually falls off, as the duration of the test increases. The passivity thus produced are explained as follows.
(1) In the case of 12 percent chromium steel, the passivity is produced by the oxidizing power of the nitric acid solution, after being etched away the “shattered” metal which is difficult to render passive.
(2) In the case of 10 percent chromium steel, the passivity is due to the oxidizing power of Fe⁺⁺⁺ ions which is produced by attack and accumulated around the specimen (if specimen is rotated and Fe⁺⁺⁺ ions are scattered, the passivity can not be obtained).

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Alloys of the Ni-Sb system throughout the whole series have been very carefully investigated by thermal analysis, thermomagnetic analysis, electric resistance and differential dilatometric measurements as well as microscopic examination, and a new diagram, quite different from the one heretofore known, has been proposed from the results of these studies which are summarized as follows:-
(1) The liquidus consists of seven branches with two maxima.
(2) In the solid state there exist seven phases, α, β, γ, δ, θ, ζ and ε.
(3) In the liquid state there occur following eutectic and peritectic reactions.
L_??_α+β, 64% Ni, 1097°.
L_??_β+γ, 45% Ni, 1070°.
L_??_ζ+ε, 1.5% Ni, 616°.
L+γ_??_ζ, 16.16% Ni, 626°.
(4) In the solid state there occur following peritectoid and eutectoid reactions.
α+β_??_δ, 59.12% Ni, 698°.
β+γ_??_θ, 52.93% Ni, 588°.
β_??_δ+θ, 55% Ni, 533°.
(5) α phase is the solid solution of antimony in nickel which dissolves fairly large quantity of the former, although changes in solubility with temperatures are very slight, the solubility limit at the eutectic temperature (1097°) being 16.0% Sb and increasing to 17.0% Sb at room temperature.
(6) β phase is formed directly from one of the maxima, mentioned above, which corresponds to the compound Ni₅Sb₂, and it decomposes into δ and θ phases at 55.0% Ni and 533° by the eutectoid reaction, β_??_δ+θ.
(7) The β phase is stable only at high temperature, and it changes directly into an intermediate phase β' even by a rapid cooling.
(8) δ phase is newly found by the author. Its basis is the compound Ni₃Sb, which is formed at 59.12% Ni and 698° by the peritectoid reaction, α+β_??_δ, and it has a small solubility range.
(9) θ phase is also a newly found phase, the basis of which is the compound Ni₇Sb₃. This phase is formed at 52.93% Ni and 588° by the peritectoid reaction, β+γ_??_θ, and it has also a narrow range of solubility.
(10) γ phase is formed directly from one of the other maxima, mentioned above, corresponding to the compound NiSb and has a wide range of solubility, which changes noticeably below the eutectic (1070°) and peritectoid temperatures (588°).
(11) ζ phase is formed at 16.16% Ni and 626° by the peritectic reaction, L+γ_??_ζ, and its basis is the compound Ni₂Sb₅, which has a small range of solubility.
(12) ε phase is the solid solution of nickel in antimony but its solubility range at room temperature is almost negligible.
(13) The magnetic transformation point of nickel (380°) lowers in the α solid solution with addition of antimony down to 58°, and in the two phase field of α+δ, the magnetic change occurs all at 58°.

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Ueber der Richtungsabhängigkeit (Anisotropie) der mechanischen Eigenschaften von kaltgewalzen Homogeneblechen sind viele Arbeiten vor vorgelegen, aber die von Medial-und Grobfluβeisenblechen sind noch nicht vollbracht. Es wurden daher weitere Versuche an verschiedene Schiffsfluβeisenblechen ausgeführt.
Die Richtungsabhängigkeit der Festigkeitseigenschaften und Kerbschlagzähigkeit wurde mit der unter einem Winkel von 0°, 22.5°, 67.5° und 90° zur Walzrichtung entnommenen proben untersucht.
Zur Bestimmung des Einflusses der Glühtemperatur auf die Richtungsabhängigkeit der mechanischen Eigenschaften und den Gefügeaufbau wurden die Proben je 1h. bei 450°, 700°, 900° und 1, 000°., und 3h. bei 1, 000°. geglüht.
Die Festigkeit, die Dehnung, die Brucheinschnürung, die Streckgrenze und die Kerbschlagzähigkeit in der Abhängigkeit vom Winkel zwischen Probenlangsache und Walzrichtung zeige ich mit der Abbildung.
Die Hauptversuchergebnisse sind folgendes:
1) Bei Schiffsfluβeisenblechen wurde ein starke Anisotropie der Festigkeitseigenschaften und Kerbschlagzähigkeit gefunden.
2) Die Richtungsabhängigkeit der mechanischen Eigenschaften von Medial-und Grobfluβeisenblechen erklärtsich nicht durch der Gefüge.
3) Der Einfluβ der Glühtemperatur auf die Richtungsabhängigkeit der mechanischen Eigenschaften kann für verschiedene Blechen schwächer verschieden sein, und durch einzelne Glühung bleibt hier eine Anisotropie.

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As it was found in the 2nd Report (Jour. Iron Steel Inst. Japan, 24 (1938), 34) that the addition of Ca, Sr, Ba and as improves the corrosion resistance of the Mg-Cd alloys conspicuously, more detailed experiments in the range of 0-8% of Cd and 0-1.2% of Ca have been carried out of the corrosibility, mechanical and electrical properties of the Mg-Cd-Ca alloys. The results obtained may be summarised as follows:
The composition of the alloys which have comparatively high resistance against corrosion lies in the range of 0-5% of Cd and 0.2-0.8% of Ca. Although no high tensile alloys may be expected in this alloy system even when they are heat treated, the addition of Ca increases generally the hardness of the alloys. The electrical resistance of the Mg-Cd system decreases in the first place with the addition of Ca, owing perhaps to the fact that the latter element acts as a refining reagent of the molten alloys.

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