Single crystals of ferromagnetic semiconductor CdCr₂S₄ are grown by a vapor-liquid transport method, and their crystallographic and magnetic properties are characterized. The magnetic properties scatter rather widely, which is discussed in relation to the nonstoichiometry in the compound. The results are summarized as follows.
(1) Using CdS and CrCl₃ pellets in the mole ratio 2 : 1, CdCr₂S₄ single crystals are grown by the vapor-liquid transport for 4 days at the source and the growth zone temperatures 985 and 950°C, respectively. The single crystals obtained are octahedral and have a maximum side length of 4 mm. Larger octahedral CdCr₂S₄ single crystals having a side length of about 5 mm are grown by winding a platinum ribbon on the CrCl₃ pellet.
(2) Curie constant C and paramagnetic Curie temperature θ range from 3.40 to 4.50 emu · deg/mol and from 141 to 165 K, respectively. This scatter is attributed to the difference of nonstoichiometry in the compound.

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The deformation characteristics of (211)[\bar111] single crystals of α-brass during rolling have been studied. It is shown that when substantial mechanical twinning occurs, the (211)[\bar111]+(255)[5\bar1\bar1] orientation changes gradually into the {111}⟨211⟩ duplex orientation. At this stage of rolling some banded regions with heterogeneous deformation (shear bands) are formed. Although the traces of the shear bands are not in accord with those of the {111} slip planes, macroscopic shearing deformation occurs in the crystal. It was concluded that this deformation behavior would govern the occurrence of the duplex {111}⟨211⟩ orientation. With increasing rolling reduction, the volume fraction of the shear bands tends to increase, and at reductions above about 90%, the greater part of the crystal is occupied by shear bands. The occurrence of the {011}⟨100⟩ and {011}⟨211⟩ orientations in the rolled crystal is ascribed to the development of deformation textures within the regions of shear bands during rolling of higher reductions.

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Twinning mode and twinning stress in Cu-8 at%Al single crystals have been examined as a function of crystal orientation in the temperature range from −196°C to room temperature. The main results obtained are summarized as follows: (1) Twinning mode strongly depends not only on the crystal orientation but on the deformation temperature. (2) Twins are generally nucleated along the slip planes with the maximum resolved shear stress at the intersections between the twinning planes and the well-developed slip-bands. Those well-developed slip-bands also act as obstacles for the growth of twins. (3) Twins are formed along the cross slip-planes as well as along the conjugate and primary slip-planes at −196°C. (4) The twinning stress depends not only on the prestrain for the twinning but on the twinning mode.
The results are discussed with a twinning model proposed by the present authors.

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In order to study the orientation dependence of the Bauschinger effect, compressive flow behaviour of aluminium single crystals with various orientations prestrained in tension up to τ_p=300 g/mm² (τ_p: shear stress on the primary slip plane) was investigated at room temperature. Several kinds of parameters to evaluate the Bauschinger effect in terms of the stress, strain and energy were measured at various stages of the reversed straining.
The parameters determined at relatively early stages of the reversed straining decreased with increase in the Schmid factor for the primary slip system. On the other hand, the parameters obtained at later stage showed a different orientation dependence. These results support the conclusion, given in a previous paper, that one should be very careful in comparing the results by different authors.
It is generally accepted at the present stage of investigation that the Bauschinger effect originates from the elastic interactions among dislocations introduced during prestraining. Hence, the parameters determined at early stages may be more suitable for the estimation of the direct influence of dislocation structures due to prestraining on the Bauschinger effect. Moreover, optical microscopy of specimen surfaces after prestraining showed that the glide on the secondary slip planes occurred more frequently in crystals with lower Schmid factors. On these bases the Bauschinger effect may be concluded to decrease with an increase of the Schmid factor, that is, the effect is smaller in crystals oriented for a single glide than in those oriented for multiple glide. Such orientation dependence of the effect may be explained in terms of the change in ρ_m·\barl, where ρ_m and \barl are the density and the mean path of dislocations which move back upon the stress reversal, respectively.

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Theoretical studies of the localized electronic structure and the bonding mechanism around impurity carbon atoms in titanium metal and for titanium monocarbide are made using the Hartree-Fock-Slater molecular cluster model. Orbital energies and results of Mulliken’s population analysis are presented for Ti₁₈, Ti₁₈C and Ti₁₄C₁₃ clusters. Density-of-states curves for the Ti₁₄C₁₃ cluster are in good agreement with the photoelectron and soft X-ray spectra. Overlap populations are used to discuss the covalent bonding in these clusters. The effect of self-consistency for Ti₁₄C₁₃ cluster is also investigated.

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Electron microscope observation was made on a Mg-base Friauf-Laves phase Mg(Cu_1−xAl_x)₂ with x=0.465. As-cast specimens exhibited mainly a 4-layer type structure, and annealed ones a 9-layer type. In addition, small regions with other layer types such as 2-, 6-, 10- and 16-layer types were also observed. Two new stacking variants having 6- and 16-layer type structures were analysed by comparing diffracted intensities with calculated ones. The 6-layer type structure is expressed as ABC′B′AB′ in terms of the six compound layers of the Friauf-Laves phase. The space group is P\bar6m2 with a unit cell of dimensions a=5.10 and c=25.0 Å. The 16-layer type structure is expressed as ABC′BCA′CAB′A′CA′C′BC′B′ having a space group P6₃/mmc with lattice constants a=5.10 and c=66.7 Å.
The lattice images of the 2-, 4-, 6-, 9-, 10- and 16-layer type structure were obtained by using a direct beam and several reflected beams. A remarkable correspondence was found between the lattice image and the layer sequence.

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Transmission electron microscopy and electron diffraction studies have been carried out in order to make clear the crystallography and morphology of strengthening phases in a dental gold alloy, Au-35.4 at%Cu-17.8 at%Ag-9.7 at%Pd. Age-hardening observed in this alloy is caused by the formation of the AuCu I type tetragonal superlattice nuclei on the disordered matrix {100} planes. The interfacial coherency between the AuCu I type superlattice and the disordered matrix has been studied by referring to diffuse scattering in diffraction patterns and striated contrasts observed in the electron micrographs. The significant hardness increase is considered to be associated with the striated contrasts due to the tetragonal distortion. The structure of the final state has been identified as the AuCu I type ordered platelets which have the c-axis distributed along the three cube axes and have the [011] twin relation. Nodular precipitates formed at grain boundaries play no important role in the age-hardening.

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In analyzing niobium in low alloy steel with an emission spectrochemical technique using Nb II 3194.977 Å as an analytical line, it was found that higher experimental values were obtained in spite of the absence of known interference line. The values of 0.004% to 0.007% were, for example, found in spite of the absence of niobium in the steel samples. Studying the cause, we found the following facts ; (1) The precision (σ_d) was low for the steel sample containing much manganese. (2) A spectral line of manganese is present at the wavelength position of about 3194.87 Å in the vicinity of Nb II 3194.977 Å. (3) The interference can be corrected by the following formula; ΔNb(%)=0.0034×Mn(%)−0.0020 (Mn>0.80%)

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Although a great deal of work has been performed on the dependence of strength and toughness on grain size in steels, the grain boundary properties in connection with strength and toughness remain unclarified. In order to study the grain boundary properties, the specimen fracturing device developed in the authors’ laboratory was incorporated in the ion microprobe mass analyzer. Utilizing this device, specimens can be fractured mechanically in high vacuum and the distribution and segregation of various elements at grain boundaries can be assessed quantitatively. The practical application of this device to the study of grain boundary segregation of Fe-1.5%Sn and Fe-3%Mn-0.4%Mo steels is described.

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The optical constant for the film-free surface of 18–8 stainless steel was determined by the ellipsometric measurement in dehydrated methanol immediately after the film removal treatment in a 0.5% bromine-methanol solution.
Using this optical constant of the film-free surface, the ellipsometric parameters, Δ and Ψ, measured for the steel in 1M–Na₂SO₄ of varying pH under potentiostatic control were analyzed and the optical constants and thickness of passive and transpassive films were determined. The optical constants of these films were dependent on the pH of solutions and closely related to the difference in film composition. The thickness of passive film and its increase rate with potential also depended on pH and became larger with increasing pH.

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In order to determine suitable electrolytes for the electrorefining of vanadium or electro-extraction from soluble anodes, the freezing points of the following systems were measured by thermal analysis: KCl–VF₃ (up to 25 mol%), NaCl–VF₃ (up to 45 mol%), NaCl–KCl(equimolar)–VF₃ (up to 25 mol%), KCl–KF–K₃VF₆, and NaCl–NaF–Na₃VF₆. The phase equilibrium relations in these systems were also examined by X-ray diffraction analysis. It was found that the system KCl–KF–K₃VF₆ is a ternary eutectic type and has its ternary eutectic point at 594°C and KCl 54.8, KF 44, K₃VF₆ 1.2 mol%. It was also found that the system NaCl–NaF–Na₃VF₆ is a ternary eutectic type and has its ternary eutectic point at 661°C and NaCl 24.3, NaF 70, Na₃VF₆ 5.7 mol%.

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