The phenomenon of central bursting during cold drawing of a high-purity high-chromium ferritic stainless steel has been investigated, and it is well established that the defect forms periodically in the drawing direction and does not have the usual chevron or arrow shape but a penny shape. The defect is generated by cleavage fracture at the centerline of the billet, depending on the stress state when plastically deformed during drawing. In drawing the hydrostatic stresses are most tensile in the slipline field analysis, and the damage at a critical tensile stress is most severe at the centerline despite the small amounts of deformation and strain-hardening. The growth of defects takes places in a direction perpendicular to the highest tensile stress by discontinuous cleavage propagation to form the penny shape. Blunting of the crack tip occurs in the region directly under the die and then the crack propagation rate is retarded to stop. Mechanical properties of the high-purity high-chromium stainless steel play a very important role in the damage formation process.

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A series of Fe–Cr alloys covered by air-formed film were examined by XPS with varying degrees of the X-ray energy for exciting photoelectrons. An unevenness of the surface film could be detected by comparing spectra excited by the Al Kα and Mg Kα radiation. The results concerning the composition were explained by a fairly uniform depth distribution of all the constituents of the oxidized surface layer and the substrate alloy.

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Microstructures of the stainless-steel filament produced by glass coated melt spinning are investigated. In the filament formed by rapid quenching from the liquid state with the drawing process, micrograins of a new metastable phase having a tetragonal structure unit cell with a=2.64×10⁻¹⁰ m, c=3.55×10⁻¹⁰ m has been observed in the stable phase having the fcc austenitic structure.
These phases are transformed into a mixture of the second metastable phase and the fcc phase by heating at about 490°C and by heating above 650°C, the second metastable phase is transformed into the stable fcc austenitic phase.

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Stress dependence of creep rates and the level of internal stress, as well as transient behavior upon sudden stress changes during the steady-state creep were studied. The stress exponent for steady-state creep rates, n, depended on the stress level. In the stress region lower than 7 MPa, n was about 5 and the inernal stress was nearly equal to the applied stress. The steady-state creep in this region is controlled by a recovery process, though dislocations glide viscously. In the stress region between 7 and 30 MPa, n was about 3. In the stress region higher than 30 MPa, n became again larger than 3. In these two regions, where the internal stress was obviously less than the applied stress, the role of viscous gliding of dislocations becomes important and cannot be neglected in the discussion of the total process of creep. Transition from the middle to the high stress regions was found to arise from the change in the stress dependence of dislocation density. These results indicate that the change in n does not necessarily correspond to the change in the creep mechanism.

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The textures of Fe-3.25%Si alloys by low speed cutting (76 mm/min) were determined by X-ray diffractometion and optical gonio microscopy. In the orthogonal cutting of single crystals with various orientations, a few preferred orientations such as (011)[100] and (‾132)[201] were observed in the deformed regions from the cutting surfaces to a depth of about 50 μm. Conventional plane cutting of polycrystalline specimens of nearly random texture with 3 different grain sizes formed a texture with a major (011)[100] orientation and minor (111)[11\bar2] and (0\bar12)[\bar421] ones. The intensity of the (011)[100] main component increased and its dispersion decreased with the average grain size. Further, the main component in the cutting surfaces of the polycrystalline specimens became obvious in two-pass cutting.

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The anodic extraction of vanadium from V₂C-type anode materials (86.7–88.5 wt% V) produced by the carbothermic reduction was studied in the temperature range of 700–850°C, in the cell voltage range of 0.4–1.2 V, and in two kinds of electrolytes, KCl–NaCl–NaF–K₂NaVF₆(44–44–7–5 mol%) and KF–NaF–K₂NaVF₆(62–33–5 mol%). Of the two molten electrolytes, the latter gave a better anode current efficiency than the former. This fact suggests that fluoride ions suppress the anodic oxidation of V³⁺ to V⁴⁺ or V⁵⁺ in the electrolyte. The anode current efficiency increased with an increase in bath temperature. The pores in the anode materials were remarkably effective in increasing the anode current efficiency and the extent of extraction of vanadium. The V₂C anode changed to the VC phase and free carbon as a result of the extraction of vanadium. The electrolysis at 825°C and 1.2 V for 1, 2 and 3 h in the KF–NaF–K₂NaVF₆ electrolyte yielded 60, 72 and 86% of the vanadium extraction, respectively, corresponding to the anode current efficiency of 75, 62 and 46%.

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The anodic dissolution of vanadium from VC-type carbide was investigated in two kinds of electrolytes, KCl–NaCl–NaF–K₂NaVF₆(44–44–7–5 mol%) and KF–NaF–K₂NaVF₆(62–33–5 mol%), in the temperature range of 700–850°C and in the cell voltage range of 0.8–1.4 V. A high degree of vanadium extraction was made from the spongy vanadium monocarbide anode which was prepared carbothermically from a mixture of V₂O₅ and medium coal tar pitch. This anode did not disintegrate even at an extraction percentage of 98%. Anode current efficiency of 40–50% and a high degree of vanadium extraction were obtained under the electrolytic conditions of 1.0–1.2 V and 825°C in the KF–NaF–K₂NaVF₆ electrolyte and also 1.4 V and 725°C in the KCl–NaCl–NaF–K₂NaVF₆ electrolyte.

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Ideas expressed by some investigators on the regulating action of oxygen (aeration) in the separation of molybdenite from pyrite and chalcopyrite due to their selective oxidation and hence their selective adsorption of collector (ethyl xanthate) were shown to be partially incorrect. Experimentation with oxygen and hydrogen peroxide showed that while the former has only a slight effect on pyrite, the latter has a distinct and a perceptible effect on the adsorbability and floatability indices of all minerals tested. The activating action of oxygen on the flotation of pyrite was shown to be due to the oxidation of ferrous sites to ferric and not due to oxidation of sulphide sites to sulphate, as many investigators claim. The positive increase of electrode potentials of sulphide minerals when dipped in distilled water was shown to be due to the acidity of the latter and not due to their oxidation as most researchers suggest. Leaching chalcopyrite with H₂SO₄ solution of pH 3 imparts to it a surface with flotative properties corresponding to that of pyrite, due to the selective leaching of copper sites and the predominance of those of iron. This was successfully used to aid co-depression of chalcopyrite with pyrite. Either CuSO₄ or Na₂SO₃ could aid the selective separation of molybdenite, whereas their conjoint use gives a complex anion of the type CuSO₄SO₃²⁻, which possesses a tremendous affinity for iron sites over those of molybdenum, whence xanthate (collector) species are selectively adsorbed on the latter leading to the selective flotation and hence separation of molybdenite.

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Magnetic hysteresis characteristics and microstructure of Co–Fe–Nb semihard magnetic alloy which was heavily cold worked by more than 97.8% were investigated by means of magnetic hysteresis loop measurements and transmission electron microscopy.
The results obtained are summarized as follows:
(1) The Co–Fe–Nb alloy which is cold worked heavily by more than 97.8% reduction in area shows a peak value in coercive force when annealed at 700∼750°C for 1 h. The higher the degree of cold working prior to annealing, the lower the value of coercive force. The rectangularity of hysteresis loops becomes higher with increasing degree of cold working prior to annealing.
(2) In heavily cold worked Co–Fe–Nb alloy, spherical precipitates Co₃Nb are observed in the fcc matrix. The magnetic hardening of the alloy can be attributed to the pinning effect of the domain wall at these Co₃Nb precipitates.
The relationship between the microstructure and the rectangularity of hysteresis loops has been discussed.

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The electrochemical technique involving solid-oxide electrolyte has been used for the determination of the thermodynamic properties of SnO₂ and the activities of Sn in liquid Ag–Sn alloys at 1023 to 1273 K. The standard Gibbs energy of formation of SnO₂(c) is given by
ΔG_f°(SnO₂,c)⁄kKmol⁻¹=−578.8+0.2088(T/K)±0.8.
The third-law analysis was applied to the results for the standard Gibbs energy of formation of SnO₂. The activities of Sn and Ag at 1023 and 1173 K were determined as a function of alloy composition.

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