The experimental evidences concerning anomalous changes in various properties of zinc with temperature, in solid as well as in liquid state, were closely studied, and it was found that there exist eleven anomalies and that they can be classified into four groups; further that, if we take into count of the absolute zero to each of them, the temperature intervals in each are in the ratio of a sequence of natural numbers as shown in the following table.
Anomalous temperatures in °K (number in parenthesis is interval ratio).
Group 1; 0 (5) 247 (4) 443 (3) 593 (2) 692 (melting point).
Group 2; 0 (4) 473 (3) 823 (2) 1069 (1) 1178.
Group 3; 0 (2) 36 (3) 90.
Group 4; 0 ? 0.79 (transition point of supra-conduction).
It is thus seen that the anomalies at 443 °K (170°) and 593 °K (320°) which have been long discussed, as well as the others, are to be attributed to zinc itself.

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With expansion-time curves during quenching of steel obtained by Sato's Self-recording Apparatus, the isothermal transformation for 5 carbon steels containing 0.28 to 1.10% carbon and three series of steels with 0.2, 0.4 and 0.6% carbon content each alloying with 1% of manganese, chromium, nickel and silicon was studied, and the transformation temperature-time curves i.e. S-curves for these steels were determined. As quenching media molten lead, molten salt mixture of 55% KNO₃+45% NaNO₂, rape-oil and ice water which were vigorously stirred were used.
The influence of carbon content on the rate of transformation in the pearlite range is comparatively small, while in bainite and martensite ranges the transformation is markedly affected being consistently retarded with increasing carbon content. In a series of steels containing 0.24 to 0.59% carbon, 1% chromium is revealed as the most effective addition, not only for it caused complicating the S-curve but also retarding the transformation in the Ar' range.
By the addition of 1% of manganese or nickel to the hypo-eutectoid steels, the pearlite transformation is similarly retarded but the effect in the bainite range is small, in the both ranges the effect of nickel being smaller than that of manganese.
The influence of an addition of 1% silicon to a series of steels containing 0.25 to 0.68% carbon is small but for the Ar' transformation is retarded.

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A series of corrosion tests of Fe-Cr-Mo alloys containing 10%, 12%, 14%, 16%, 18%, 20%, 22% and 24% Cr with varying Mo content 1_??_46% and 0.04_??_0.25% of carbon, were carried out by the dip method. The corrosion was examined in 10% aqueous solutions of HCl, H₂SO₄, HNO₃ and H₃PO₄ at 25° and 40% aqueous solution of HNO₃ at boiling temperature by measuring the loss in weight and the extent of corrosion was expressed as mg/cm²/hour. In this system, there is a wide composition range in which superior resistivity for several acids is observable.

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In a previous paper the author suggested that there are three hardening phenomena in Duralumin alloys, namely:
(1) Primary hardening (Natural age-hardening)
(2) Secondary hardening (Natural age-hardening after “Rückbildung”)
(3) Temper-hardening (Artificial age-hardening)
The primary hardening may be explained by the theory of congregation (or aggregation) of solute atoms at certain selected positions on the Aluminium lattice, and the sudden reduction of the hardness on short period tempering at somewhat higher temperatures (“Rückbildung”, “Retrogression, ” “Intermediate softening” or “De-hardening”) may be attributed to the dispersion of the aggregated solute atoms into solid solution, and the subsequent recovery of hardness at room temperature (The secondary hardening) may be attributed to reaggregation of solute atoms by the quite same process as that occurring in primary hardening. The temper hardening takes place on the basis of precipitation of so-called “intermediate” phase or of compounds, but the maximum hardness generally is attained prior to the appearance of lamellar structure under the microscope.
According to the latest investigations by Preston, the formation of Cu-rich thin platelike aggregates are presumed when the Cu-Al alloy is aged at room temperature and there are diminution of aggregates when “Rückbildung” takes place by short period tempering at 200°, but if the tempering is continued for several hours, the thin platelike aggregates are formed again, The linear dimensions of thin platelike aggregates which were formed at room temperature are far more smaller than that of aggregates which were formed at 200°. (about 40 Å for the former, and about 4000 Å for the latter).
In the present paper the author has made a characteristic differentiation between the natural age hardening and the temper-hardening by the experimental evidence, and deduced the theory of aging.
In the above mentioned explanations there are not any differences in the opinions of the present author and that of other authors to presume the formations of thin platelike aggregates which are vary in dimensions at different temperatures (the one formed at room temperature and has smaller dimensions, the other formed at higher temperature and has larger dimension). But the presentt author suggests the opinion that there are differences not only in the dimensions of the two kinds of aggregates, but also in their coaguration of atoms in the thin platelike regions of these respective cases.
As the coaguration of solute atoms in the thin platelike region which was formed by natural ageing is far more weaker, so the sudden dispersion of the atoms would be expected by short period tempering, and this phenomenon corresponds to the “Rückbildung” The thin Plate which was formed by tempering is also an aggregate of solute-atoms, but it requires an activation energy to bring about aggregation, and the “state of aggregation” is much stable than that of the former
In the above explanation, the author deduced the theory of aging by applying somewhat same idea of adsorption theory, because the movements of solute in the, solid solution (i.e. the congregation and the dispersion etc.) are analogous to the case of adsorption.
The relationship between the two forms of aggregations is similar to that of two forms of adsorption, namely; the van der Waals adsorption (the weaker state of adsorption) and the activated adsorption (the stronger state of adsorption). The van der Waals adsorption takes place at low temperature and removed more or less completely at somewhat higher temperatures. The activated adsorption recommences at still higher temperatures, but in a different form, as the stronger state of adsorption

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In a previous work, ⁽¹⁾ the author studied the so called “Strain Aging” phenomenon of some alloys and proved that in u brass and a Al-bronze, the increase of electric resistance produced by cold work is very great and the hardening phenomenon takes place corresponding to the 1 st. decrease of electric resistance in annealing process. In order to reveal the mechanism of hardening and to study the existence of analogous phenomenon, the author made a further reserch on the annealing characteristics of cold drawn Cu-Ni, Cu-Si, Cu-Sn, Cu-Be, Cu-Mn, Ag-Cd, Ag-Zn, Ag-Sn, Al-Zn, Al-Mg alloys and pure Al, measuring electric resistance, tensile strength and hardness. For the alloys of Cu-Ni, Cu-Al, Cu-Zn systems in water quenched and annealed states, measurements of electric resistance were made at high temperature. The results obtained may be summarized as follows:
(1) The increase of electric resistance of pure Al produced by cold work is very small and is recovered at the recrystallization temperature.
(2) On annealing Al-Mg, Al-Zn, Cu-Si, Cu-Sn and Ag-Sn alloys the ordinary recovery process occured.
(3) In Ag-Cd and Ag-Zn alloys, analogous to a brass and a Al-bronze, the percentage increase of electric resistance produced by cold work is very great and the hardening phenomenon takes place corresponding to the 1 st. decrease of electric resistance in annealing process.
(4) On annealing Cu-Ni alloys of high Ni contents, the hardening phenomenon takes place. Aa a result of high temperature-electric resistance measurement, a kind of order-disorder transformation is found to take place in Cu-Ni system and it is presumed that the hardening phenomenon is due to this transformation.
(5) The anomality, presumely analogous to the case of Cu-Ni system, is found to take place in Cu-Al system and Cu-Zn system by means of high temperature-electric resistance measurement. And the hardening phenomenon of a brass and a Al-bronze is presumed to be due to this anomality.
(6) On studying the relation between the concentration of solid solution and the percentage increase of electric resistance produced by same degree of cold work, it is found that the marked discontinuous increase of electric resistance takes place from some atomic % of solute atoms in Cu-Al, Cu-Zn, Cu-Ni, Ag-Zn and Ag-Cd system.
(7) The hardening phenomenon of cold worked Cu-Be alloy and Cu-Mn alloys of high Mn % by low temperature annealing is presumed to be due to the precipitation of γ phase and a Mn.

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When steel is decarburized at a temperature below its A₃ point, a ferrite band is sometimes formed on its surface, When the band is formed, the form of the ferrite grains is either in columnar or equiaxed grains. The author studied the relations between the Fe-C equilibrium diagram and these two kinds of ferrite grains formed by decarburization.
(1) High purity steels having 0.6%, 0.9% and 1.7% of carbon were decarburized below the A₃ point by moist hydrogen and the relation between the forming of columnar or equiaxed grains and the equilibrium diagram was sought.
(a) The decarburization of γ phase or γ+Fe₃C phase forms columnar ferrite grain.
(b) The decarburization of a+γ phase or below the A₁ line forms equiaxed ferrite grain.
(2) Hypereutectoid steel of grain sizes Nos. 3, 5 and 8 were decarburized, and it was found that although the amount of decarburization was affected by grain size, the form of ferrite grains was not affected by it. The decarburization is less as the grain size becomes smaller.

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Experiments are taken for Al-Cu (5%) and Al-Mn (1%) alloys; when the temperature of addition of alloying elements is low, the grain-size is fine under a constant condition of agitation, casting, etc.

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Dieser Bericht soll einige neue metallurgische Verfahren in Vorschlag bringen, die die Zentrifugalkraft bei den erstarrenden Legierungen so bewirken, dass diese Legierungen in verschiedenen Phasen zergliedert werden.
Das eine der Verfahren bezweckt, unter Benutzung von der Zentrifugalkraft bei einer erstarrenden Legierungen, soiche Phase, welche grösseres Spezifischesgewicht hat, an einen Teil des Gefässes zu verdichten. Das wird “Phasenverdichtungsverfahren durch die Zentrifugalkraft” genannt.
Das andere Verfahren benutzt die Flussbarkeit der Schmelze. Man wird die halbgeschmolzene Legierungen in einem Gefäss mit vielen Löchelchen umdrehen. Dann werden nur die Schmelzeteile, durch die Wirkung der Zeritrifugalkraft, ausfliessen and von der Festephase getrennt. Das wird “Trennungsverfahren der Schmelzphasen durch die Zentrifugalkraft” genannt.
Als Anwendungsbeisphiele der Zentrifugalmetallurgie sind in dieser Berichte die folgenden erwähnt:
1. Raffination des Aluminium-Rückflussgutes.
2. Raffination des Kupfer-Rückflussgutes.
3. Entsilberung des Werkbleis.
4. Herstellung der ölenthaltigen Lager.

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