The cold-rolling and annealing textures of the mild steel sheets have been investigated by using their {110} and {200} pole figures after various cold reductions ranging from 10% to 95% and subsequent annealings. As a result, it becomes clear that the cold-rolling textures can be expressed by a combination of two ⟨110⟩ fibre textures, and that the annealing textures have different behaviours depending upon the preceding cold-reductions. Namely, there occurred the {111} cylindrical texture by the intermediate reduction and the rotation around (112)[1\bar10] by the heavy reduction. The differences in texture between the rimmed steel sheets and the killed ones were examined, and no qualitative differences were found between them. The effect of varing annealing conditions on the recrystallization texture was also investigated.

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Mechanical properties (tensile property, hardness and impact value) of a commercial pure titanium were measured at various temperatures. Optical microstructural and transmission electron microscopic observations were also carried out with specimens quenched in water immediately after rolling at high temperature in order to investigate the relationship between the mechanical properties and structural changes.
The results obtained are summed up as follows:
(1) The ductility and impact values of the specimens decreased with the temperature rise from room temperature to 500°C; ductility shows a minimum at 550°C, but the specimen exhibited an extremely good ductility at temperatures higher than 550°C.
(2) In the specimens rolled at 250°C and 450°C, a dislocation cell structure and a number of striations were observed by transmission electron microscopy. Differences in the microscopic feature were recognized between the twin formed by cold rolling and the twin formed by hot rolling.
(3) The relationship between the mechanical properties at high temperature and the structure changes was discussed based on the above results.

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Changes in dislocation arrangement and twin faults formation by quenching and tempering of a Ti-9% Ta alloy were investigated by means of internal friction measurements and transmission electron microscopy. It has been found that typical needle-like martensite structures were produced by quenching from the β region, and by transmission electron microscopy a number of dislocations and (10\bar11) transformation twin were observed. It is suggested from the internal friction measurements that the annihilation of dislocations and twin faults occur during tempering at about 300°∼400°C.

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Electrochemical behaviors were measured on electrodeposited nickel with characteristic preferred orientations and the effect of the surface structure on the behaviors was discussed. In the anodic polarization, the electrodeposited nickel with the (211) orientation showed a lower initial dissolution potential than the deposits with the (210) or (110) orientation. In the cathodic polarization, the hydrogen evolution potential and the reduction current density at a constant potential were higher in the deposits with the (211) orientation than in the deposits with the other two orientations. It was, therefore, probable that the deposits with the (211) orientation was chemically most reactive among the nickel electrodeposits prepared under the present electrodepositing conditions. This was in good agreement with the result of electron microscopic observation by the author, that is, the deposits with the (211) orientation showed higher densities of corrosion trenches and holes than those with the other two orientations when the deposits were immersed into the corrosive solution for a constant period of time. The corrosion-suffered areas were twin boundaries or stacking faults which put in an appearance on the deposit surface, and a few crystal defects of these sorts were observed in the deposits having the (210) or (110) orientation, while many twin boundaries appeared in the electron micrographs of the deposits with the(211)orientation. From the above point of view, it was anticipated that there would be some difference in the density of these defects by the difference of orientations. It may therefore be predicted that the difference in the density of these defects has bearing upon the chemical reactivity of elctrodeposited nickel.

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In the present study was investigated the manufacturing of vanadium-containing high-grade cast iron which used blast furnace pig iron, pig iron made from vanadium-containing iron sand, steel scrap, ferro-vanadium alloy and vanadium oxide containing slag as the raw materials.
The mechanical properties of this cast iron were made clear, compared with plain high-grade cast iron. Moreover, in the case of vanadium additions to cast iron, the addition of a ferro-vanadium alloy in the furnace resulted in a higher yield than that in the ladle, and by the refining of the vanadium oxide-containing slag and carbon, vanadium was almost completely alloyed,
The high carbon cast iron with about 3.4% carbon showed a tensile strength of about 35 kg/mm², when 0.5∼0.7% vanadium was contained.

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Relative Härte, Reifegrad and stress released heat treatment and wear resisting properties of vanadium high-grade cast iron have been found to be superior to those of plain high-grade cast iron.
By the stress released heat treatment at 500°∼600°C for 6 hours, the vanadium cast iron acquires better mechanical properties than those of plain cast iron.
The vanadium cast iron is more resistive to abnormal abrasion caused by the increase of friction velocity.

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It has been pointed out by the author that the properties of the two-phase cemented carbides are decisively affected by the tungsten content in the binder phase, i.e., the carbon content of alloys. On the other hand, it is well known that the properties are influenced by the particle size of carbide. These results show that, investigation which takes above two factors into consideration must be carried out to make clear the properties of the cemented carbides.
In the present work the properties of WC-10% Co alloys were examined, with the following results: (1) The determination of the mean particle size by the coercive force method appears to be erroneous. (2) Both hardness and electric resistivity of the alloys decrease with increasing carbon content and grain size. (3) The strength of the alloys reaches a maximum value at a definite point of the two-phase region depending on the binder composition and grain size. (4) The lattice parameter of the binder phase and the magnetic saturation of the alloys are independent of grain size. (5) However, the stability of the low-carbon alloys at high temperatures is strongly affected by grain size.

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The deformation behavior of an aged iron-chromium alloy at 470°C has been investigated by means of electrical resistivity measurements and electron microscopic observations, in order to make clear the embrittlement of the iron-chromium alloy aged at 475°C. The electrical resistivity of the aged iron-40wt% chromium alloy which was measured at the liquid nitrogen temperature increased with the aging time. The deformation substructure of the slightly deformed brittle specimens remarkably differs from the slightly deformed ductile specimens. In the former deformation twins were directly observed by transmission electron microscopy, and dislocations were found to be almost straight. In the latter the dislocations showed a rather irregular form and irregular tangles were observed sporadically.
The specimens aged for a long time at 470°C were mostly, fractured by cleavages with a few isolated regions of intergranular fractures, and many traces of twins were observed on the fracture surface. The deformation twins observed in the aged and slightly deformed specimens seem to be closely related to the embrittlement of the aged iron-chromium alloy.

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The breakaway oxidation, mainly at 850°C, of 2.5% tin-zirconium alloy in oxygen has been investigated by thermogravimetric measurement, electron microscopic observation, electron-probe microanalysis and X-ray diffraction analysis. In the post-breakaway stage, the oxidation kinetics was remarkably affected by the pressure of oxygen, and severe cracking of the oxide film was observed. The electron-probe microanalysis and X-ray diffraction analyses indicated that the tin in the alloy was precipitated as an intermetallic compound of ZrSn at the oxide/metal interface, and suggested that the oxide film has a multilayer structre consisting of ZrO₂ and (ZrSn)O₂ layers. The mechanism of the pronounced breakaway phenomenon of tin-zirconium alloy was discussed on the basis of the behavior of tin in the alloy, and it was concluded that stress between the layers of ZrO₂ and (ZrSn)O₂ induced the cracking of the oxide film and permitted the increased oxidation.

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Quench-ageing of iron-nitrogen alloys containing about 0.02% of nitrogen was studied by electrical resistivity measurement and transmission electron microscopy. Electrical resistivity measurement of Fe–0.014% N alloy during the 10 deg–15 min isochronal annealing after quenching from 720°C revealed that the metastable iron nitride, α″–Fe₁₆N₂, precipitated around 120°C initially and redissolved completely at 230°C prior to the precipitation of stable iron nitride γ′–Fe₄N. Resistivity measurement during the course of isothermal annealing of Fe–0.022% N alloy also confirmed the reversion of the α″ phase at 242°C. Transmission electron microscopy gave direct evidence that the α″ phase initially disappeared by annealing at about 230°C. The reversion phenomenon mentioned above is explained in terms of the solubility limit of the metastable iron nitride and by the fact thet the α″ phase does not act as a nucleus for the γ′ phase.

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Very little systematic investigation has so far been made on the inter-diffusion in liquid phases, especially in high-temperature melts, as compared with the study in solid phases, because of the experimental difficulties and the limited knowledge of liquid structures. Any method which permits a closer study of the diffusivity and the mechanism of diffusion should, therefore, be welcomed. In order to clarify the relative importance cf various factors for the inter-diffusion in liquid phases, diffusion coefficients in dilute Cu–S, Cu–Se and Cu–Te liquid copper base alloys have been measured with a modified capillary-reservoir method in the temperature range from 1100° to 1300°C.
From the re-examination of the applicability of simplified equations for the calculation of the diffusion coefficient, it has been found that the equation derived by Derge et al. can only be used when the ratio of C_a⁄C_s, the ratio between the average concentration of the sample and the concentration of the reservoir liquid, is less than 0.6 or θ (=π²D_t⁄4l²)<0.7. On the other hand, the equation used by Swalin is applicable when the ratio C_a⁄C_s is larger than 0.5 or θ>0.5. To obtain the diffusion coefficient as accurately as possible, the experimental conditions, i.e. the time of diffusion and the length of the capillary, were controlled so that the ratio of C_a⁄C_s might be in the range of 0.4 to 0.6 in consideration of the analytical error. The results obtained are summerized as follows:
(1) The diffusion data fit the following Arrhenius-type equation within the limits of experimental errors.
For Cu–S system: D_C=2.0×10⁻²exp(−14500⁄RT)cm²⁄sec
Q=14.5±1.4kcal/mole.
For Cu–Se system: D_C=4.0×10⁻³exp(−11900⁄RT)cm²⁄sec
Q=11.9±1.6kcal/mole.
For Cu–Te system: D_C=3.4×10⁻³exp(−12800⁄RT)cm²⁄sec
Q=12.8±2.3kcal/mole.
(2) The diffusivity increases (D_S>D_Se>D_Te) as the radius of a diffusing particle decreases (r_S<r_Se<r_Te). The result indicates that the size of the diffusing particle is an important factor for inter-diffusion.
(3) The apparent activation energy for inter-diffusion may be expressed as a function of the activation energy of self-diffusion of a solvent and the electrostatic interaction energy between solute and solvent. The values calculated from the following equation show a fair agreement with the experimental values.
(Remark: Graphics omitted.).

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Commercial pure iron was decarburized in wet-hydrogen atmosphere after grain size adjustment, charged with nitrogen or carbon and tested by the tensile testing machine. The nitrogen or carbon content was determined by means of internal friction measurement. The yield stress, aging index, yield point elongation and other tensile properties were measured as a function of nitrogen or carbon content. Also at definite strains, the relaxed stress was measured which is the strain rate dependent part of flow stress. This part was analysed by Johnston’s theory and the stress exponent n, and the stress required to move a dislocation with unit velocity τ₀ were calculated as a function of nitrogen or carbon content. The relation between this theory and Conrad’s was also discussed.

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