It seems that the temperature Variation of Young's moduli of superlattice alloys such as Cu₈Au and CuZn is similar to the variation of the degree of order in these alloys. So far as I know, there is no known theoretical explanation for this fact. Therefore I have developed a theory for the case of CuZu (β Brass) which can explain this fact in some degree, basing upon the Bragg-Williams' approximation.
The results thus obtained are compared with the experimental results of Rinehart, regarding to the [110] direction of a single crystal, and of Köster for the polycrystal. A fair agreement is found between the present theory and the experiments just refered to. The anisotropy of Young's mcdulus can be also explained in some degree.

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The magnetic properties of Iron-Silicon-Nickel alloys in weak field has been measured at various temperatures. The result show that the alloy containing about 10% Si, about 16% Ni and balance Fe, namely, Sepermregion, shows an abnormal change cf magnetic properties at near 300°C and 550°C, and any alloys except the Senperm region of Fe-Si-Ni system has no abnormality, at near 300°C.
It is expected that in this abnormality, the former (near 300°C) is intimately connected with the formation of superlattice and the latter (near 550°C) is Hopkinson effect.

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In the first report, the magnetic properties of Fe-Si-Ni alloys in weak field had been measured at various temperatures. Now, the same measurements were caried out for the specimens quenched in oil from 550° and 350°. The results are similar with those of the previous experiments, but abnormality at about 320° shifts to low temperature at about, 80° and 30° respectively. In consequence, the minimum points on the curves of coercive force various temperature shift by same degree. However, the specimen out of “Sanperm” range exhibits no abnormality at any temperature except for Hopkinson's effect as in the previous experiment.

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(1) Ionic lattice energies of several slag components were calculated by two methods: (2) Approximating method by Huggins & Kuan-Han Sun was as useful as the more or less complex method by Bo_??_n & Harber cycle. (3) Scratch hardnesses of MnO•SiO₂ and (MnO)₂•SiO₂ were measured and they were found to be related to ionic lattice energies.

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The conclusion derived in the first report was applied to the present experiments and the condition for the formation of oxide powder on the oxide film of pure iron has been determined as (θ-317)l=48, where θ(°C) is the heating temperature, and l (h) the heating period until the powder begins to form. From the consideration for this relation, the present writer has reached the following view: -for any metals and alloys oxidized in the same process as in iron, the condition will be generalized as (θ-θ₀)l=C, at least, at temperatures not so high, where and C are, the constants characteristic to the θ₀ material, and this equation means that the larger the constants, the more difficult is the oxidation.

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The experiment was carried out on nine specimens containing various %-ages of C and Si. They were dipped in Pb bath kept at varicus constant temperatures, and for certain hours. Then they were quenched in cold water and examined under the microscope. It was found that log t and 1/T have linear relations, and that these lines are nearly parallel to each other.
(t is the time of graphitization, T is the absolute temperature of graphitization)

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The recrystallization of metals and the effect of the additional thetal on it were examined by n eans of the vertical type twisting machine mentioned in the first report. In the detenmination of recrystallizzation of pure metals and of peritectic systems, two types in their recovery were distin, guished; namely marked and discontinuous recovery. The results of temperature function are: -the recrystallization velocity of the alloys exceeds that of pure metals and the proceeding of the recry stallization of the former is relatively discontinuous compared with the latter. As to the effect of the additional metals on recrystallization, difference m the obtained curves was reccgnized, indeperdent of the solubility limit in the equilibrium diagram.

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The die blocks in use by the forging industry have three fundamental factors to consider, namely, heat, impact and abrasion. Herein the author reports the various mechanical properties of the proper and substitute die block steels at various temperatures ranging from room temperature to 700°. Proper steels wire used before the war and substitute steels during the war in Japan.

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I succeeded in extending Woodvine's fatigue theory over the tensile properties of case hardened steel (mild carburized), technical cohesion strength was induced. I concluded that case hardened layer prevented the inner layer to slip (or to yield), and made three stages of tensile properties with case depth; 1 st; true breaking strengthe's lowering, 2 nd; the technical cohesion strength of inner layer, 3 rd; the tensile strength increase only by the case hardened layer. (Carbon and chrom steels were used).
The value of technical cohesion strength by this method is lower than that of the notch method by Kuntze, this depends on the residual stress. Why case hardened layer in my calculation has an assumed higher tensile strength than solid high carbon steel depends on the residual stress. Then, I measured the residual stress of the test pieces and made clear that these were founded on the tension residual stress in the inner layer and the compression residual stress in the case hardened laver.
Next, I tried to extend the Woodvine's fatigue theory to the tensile test pieces with various notch radius. Without the case hardened layer it coincided with the experimental results of low carbon steal by Kuntze, while with case hardened layer it approached the value of the calculated result by Neuber, but their case depths are sufficiently deep to increase their tensile strength only by the case hardened layer.

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Corrosion of 18 Cr-. 25 Cr- and 30 Cr- stainless steel in the mist of 10%, H₂SO₄, and the influence of small amounts of Ni, Mo and Ni-Mo on the corrosion of them were tested.
We found that the higher the Cr content in steel is the better the resistivity; the co-existerce of Ni and Mo produces good effects on them.

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The tarnish-resisting properties of silver alloys containing a considerable quantity of zinc, tin, aluminium or cadmium (total amount being about 1_??_6%), were investigated. The addition of tin and zinc (4_??_6%) was found to hignly improve the tarnish-resisting properties of silver alloys, and also the oxide film rich in alumina formed by the preferential oxidation of aluminium containing silver alloys due to the heating in low pressure (0.01mmHg) was found to be protective against tarnishing. The solid solubility of beryllium and silicon in silver was also determined.

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The colorimetric determination of nitrogen in steel using Nessler's reagent was studied. The sample was dissolved in acid and oxidized with hydrogen peroxide, iron was precipitated with sodium hydroxide and separated by a centrifugal machine. From this solution the nitrogen was determined colorimetrically using Nessler's reagent. The microquantity of nitrogen in steel below 0.01 percentage can be determined by this method and the time required for this analysis is about 30 minutes, so this method is suited for rapid analysis in the steel plant.

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