Interfacial energies between the fcc(111) plane and bcc lattice planes such as (100), (110), (111), (210), (211), and (310) planes have been calculated using a simple interaction energy. The interfacial energy varies with azimuthal angle in the interface and the atomic diameter ratio of bcc to fcc, α. From geometrical considerations of the atomic configuration at the interface azimuthal angle was fixed in several cases and the interfacial energy versus α was obtained for each interface. The interfacial energy shows some energy valleys at the specific values of α. By comparison of the depths of the energy valleys in each interfacial energy versus α curve, we can predict the preferred orientation relationships in bcc metals on the fcc(111) surface. The results show that not only bcc(110) plane but also other lattice planes can appear on the fcc(111) surface as the epitaxial orientation relationship.

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Amorphous Fe–Al–B–Si alloys have been found to exhibit a glass transition phenomenon before crystallization. The composition range in which the glass transition is observed extends from 3 to 20%Al and 25 to 28%(B+Si) for Fe_{100−x−2.8y}Al_xB_ySi_1.8y, and 12 to 23%B and 7 to 16%Si for Fe_93−x−yAl₇B_xSi_y. The glass transition temperature (T_g) increases from 793 to 836 K with increasing B and Si contents and there is no distinct change in T_g with Al content. The largest values of the temperature span ΔT_x (=T_x−T_g) between crystallization temperature (T_x) and T_g and the change in specific heat by the glass transition (ΔC_p,s→l) are 36 K for Fe₆₅Al₁₀B₁₆Si₉ and 12.8 J/mol·K for Fe₆₅Al₇B₁₈Si₁₀. The appearance of T_g for the Al-containing alloys implies an increase of the stability of the supercooled liquid against the precipitation of crystalline phases. The increase of the thermal stability is inferred to originate from the development of a more homogeneously mixed disordered structure through an optimization of the atomic size ratio resulting from the existence of Al with the largest atomic size.

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The Kirkendall effect and movement of the α⁄β interface in Cu-45 at%Zn β brass diffusion couples were investigated by use of a multiple marker method. After anneal a bend of the multiple marker array was observed at the α⁄β interface. This phenomenon was analyzed with the aid of the frame of the reference for diffusion.
The bend of the multiple marker array arises from lattice plane formation due to vacancy creation at the interface moving by reaction diffusion. Interfacial reaction consists of atom shift between α lattice and β lattices contacting each other and arrival of atoms by interchange with the vacancies created at the interface.

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Analytical electron microscopic studies have been carried out in the rapidly solidified Al₆₅Cu₂₀Fe₁₅ alloy to relate the phase constitution and microstructure of the stable quasicrystal. The quasicrystalline phase was found to coexist with two distinct crystalline phases, one based on orthorhombic AlCu and the other based on monoclinic Al₃Fe binary intermetallic compounds. The quasicrystalline phases in proximity to each of these were of different compositions as compared to that of the bulk of the quasicrystalline phases. A spread in the short range order, stabilized by the presence of defects could result in the observed variation in the chemical composition of the quasicrystalline phase; this in turn could result in the nucleation of crystalline phases outside the composition range of the quasicrystalline phase.

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The precipitate structure of the intermediate phase β′, as well as the secondary defect structure, in an Al-8 mass%Mg alloy was observed from a very early aging stage mainly by means of TEM. The nucleation process of β′ was revealed to be strongly affected by the cooling rate during solidification. When the cooling rate during solidification was high enough, i.e., absence of porosity, regular-tetrahedron-shaped voids were newly observed as secondary defects. Some of these voids happened to be nucleation sites for β′ and thus the precipitate density was relatively high. On the contrary when the cooling rate was low, i.e., presence of numerous porosities, voids were replaced by dislocation loops which played no role in the nucleation process, so that the precipitate density was extremely low. In addition, a solutionization under water vapor stream resulted in a substantial increase in precipitate density owing to the enhancement of the efficiency of voids as nucleation sites. Consequently, void formation was thought to be promoted by hydrogen which was dissolved into the matrix during solidification. The nucleation of β′ on a void was suggested to depend on the hydrogen segregation onto the interface between β′ and the matrix, as well as on the morphology of β′. Finally, the present conclusion putting forward the effect of dissolved hydrogen on precipitation could also provide a successful explanation for the reported difference in precipitate density between the surface and the core regions of a rolled sheet.

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Transformation behavior in Ti₅₀Ni_50−xCu_x (at%) alloys has been investigated by carrying out X-ray diffraction in the temperature range between 343 and 83 K, and the following was found. In the alloys with Cu-content less than 5 at%, B2→B19′ transformation takes place. In the 7.5 at%Cu alloy, both B2→B19′ and B2→B19→B19′ transformations take place. In the alloys with Cu-content between 10 and 15 at%, B2→B19→B19′ transformations take place. The B19→B19′ transformation is not complete even at 83 K in alloys with Cu-content more than 10 at%, while complete in the 7.5 at%Cu alloy. In the 20 at%Cu alloy, only B2→B19 transformation takes place. This transformation behavior is consistent with that obtained from electrical resistivity and DSC measurements.
Lattice parameters of the parent and martensite phases were obtained from X-ray diffraction and the lattice deformation was calculated by using the parameters. In relation to the calculated lattice deformation, the transformation elongation and hysteresis observed in thermal cycling tests under a constant load were examined, and the following was found. Cu-content dependence of the transformation elongation originates from that of the lattice deformation. The decrease in transformation hysteresis with increasing Cu-content originates from a decrease in friction against the movement of the interface between the parent and martensite phases.

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Void formation on grain boundaries in Cu-9.7 mass%Zn alloy has been investigated in connection with the grain boundary character. The alloy was prepared by melting electrolytic copper and pure zinc (99.9%) in high purity argon gas atmosphere. The ingot was hot rolled at 1093 K and then cold rolled to 1 mm in thickness. Tensile tests were performed on an Instron type testing machine in argon gas atmosphere. The initial strain rates were 3.5×10⁻³, 3.5×10⁻⁴ and 3.5×10⁻⁵ s⁻¹. The microstructure and fracture surfaces of the specimens were observed with an optical microscope and a scanning electron microscope. Grain boundaries were characterized from their boundary misorientations by analyzing ECPs (Electron Channeling Patterns) taken from two grains.
A ductility minimum appeared at 673 K at any strain rate and the elongation to fracture decreased with decreasing strain rate. The observed ductility loss is attributed to the initiation, growth and coalescence of voids on grain boundaries during deformation. This void formation occurred at a smaller strain with increasing test temperature. The minimum sigma value of the cavitated coincidence boundaries was 31 when deformed at 673 K and the initial strain rate of 3.5×10⁻³ s⁻¹. Meanwhile, the sigma value was as small as 9 at the initial strain rate of 3.5×10⁻⁴ s⁻¹. Therefore, it was suggested that the strain rate affected the relationship between the propensity to void formation and the grain boundary character.

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The diffusion coefficients of CuCl₂, FeCl₃, and Fe₂(SO₄)₃ in acidic aqueous solutions were measured at 298 K using a diaphragm-cell method. Also the diffusion coefficients of CuCl₂ in water were determined at the same temperature. The data obtained are listed as a function of the molar concentrations of the solutes. The diffusion coefficients of CuCl₂ in water are larger than those of CuSO₄. The concentration dependency of the diffusion coefficients for CuCl₂ in water could be explained in terms of the changes in the mean activity coefficients of CuCl₂ and in the viscosity of the solutions. The diffusion coefficients of CuCl₂ in aqueous HCl solutions are larger than those of FeCl₃. The presence of HCl has a significant influence on the diffusion of CuCl₂ and FeCl₃, and it decreases their diffusion coefficients. On the other hand, the diffusion coefficients of CuSO₄ in aqueous H₂SO₄ solutions are larger than those of Fe₂(SO₄)₃. However, the presence of H₂SO₄ have no significant effect on the diffusion coefficients of Fe₂(SO₄)₃. The effect of HCl and H₂SO₄ on the diffusion coefficients of CuCl₂, FeCl₃ and Fe₂(SO₄)₃ were discussed based on the predominant diffusing species and the diffusion potential due to the H⁺ ions migration.

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The fundamental parameter (FP)-XRF analysis of ten alloying elements (Al, Ti, Cr, Mn, Fe, Co, Zr, Nb, Mo and W) in nickel-base heat-resisting alloys was performed with the XRF-11 program.
One nickel-base alloy for multi-elements calibration standard was prepared by a vacuum arc melting method. The homogeneity test of alloying elements in the disk standard was performed by spark emission spectrochemical analysis. Consequently, the standard could be used for the FP-XRF analysis calibration. The chemical composition of the calibration standard was determined by the wet chemical analyses and inductively coupled plasma atomic emission spectrometry after ion-exchange separation.
The spectral line overlaps, that is, m_Mn,Cr, m_Co,Fe, m_Nb,Mo and m_Mo,Zr were 0.0004, 0.0003, 0.0004 and 0.0030, respectively. The accuracies for the determination of alloying elements with the proposed method obtained from fifteen standard reference materials were almost equal to those obtained by the correction method using theoretical alpha coefficients. The relative standard deviations (RSD) of repetitive seven measurements for the analytical values of the ten alloying elements were within about 1.5% with the exception of those for manganese (Mn; 0.01%, RSD; 6.08%) and tungsten (W; 0.06%, RSD; 6.69%).

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Electromotive force (EMF) measurements using ZrO₂ solid electrolyte were carried out in the Ba–Y–Cu–O system. Gibbs free energies for the reaction in the cell electrodes were summarized in the equations with linear temperature dependency. The standard free energies of the formation of Y₂Cu₂O₅ and YCuO₂ were derived from EMF data and compared with published informations on the stability of Y₂Cu₂O₅.
From the results of the X-ray diffraction measurements for the quenched specimens, the phase equilibria in Y–Cu–O system were determined in the temperature range 923 K to 1223 K. Based on the experimental results, YCuO₂ was stable above 1115 K and at the oxygen partial pressure higher than 7.18×10⁻⁴ Pa. In the quaternary Ba–Y–Cu–O system, only a few cell could show the stable EMF. The solubilities of barium in both Y₂Cu₂O₅ and YCuO₂ were negligibly small.

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Surface segregation in an Fe-20 mass%Cr single crystal alloy was investigated by using Auger electron spectroscopy with in situ heating. Segregation of chromium to the free surface took place by heating above about 750 K. The experiment of the segregation kinetics showed that the segregation process was controlled by diffusion of chromium in the alloy. In spite of the low concentration of residual nitrogen in the alloy, remarkable surface segregation of nitrogen was also observed. It was shown that the segregation of nitrogen was strictly correlated with that of chromium through the segregation process. It may result from an attractive interaction between chromium and nitrogen in the segregated layer on the surface. A model for the segregation behavior was proposed, and the effect of the interaction between solutes on the interface segregation was discussed with previous results.

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Residual stresses in aluminum bar specimens cold-drawn to cross-sectional reductions from 23 to 81% were measured. The preferred orientation of each part of the cross-section for these specimens was measured.
It was shown that the preferred orientations in each part examined were changed by drawing, and the changes were closely correlated with the residual stress. The effects of the fiber texture on the generation of residual stresses were investigated.
A rather high residual shearing stress which is connected with the normal directional residual stress was produced on the surface and in the neighboring inner part. It corresponded well to the structural microstrain developed in the texture of each part of the section caused by the plastic deformation.

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The effects of alloying elements on dispersion of SiC particles into molten aluminum were investigated. The time required for incorporation of SiC particle into molten aluminum was defined as an incorporation time. The incorporation time of SiC was shortened by alloying magnesium, or by alloying titanium together with tin. These alloying elements have strong affinity for SiC and are able to form silicide as a result of reaction with SiC. Magnesium silicide was detected by EPMA, although the existence of titanium silicide could not be conformed. The incorporation time of SiC was prolonged by adding zinc, copper and tin which have no affinity for SiC. Moreover, particulate dispersion is considerably influenced by surface-active elements. The incorporation time of SiC particle was shortened by adding lithium which is a surface-active element with strong affinity for SiC, whereas it was prolonged by adding surface-active elements with weak affinity for SiC such as lead and bismuth. This is probably because lead and bismuth adsorb at the interface and hinder the wetting between SiC particle and molten aluminum. The addition of silicon into aluminum prolonged the incorporation time of SiC because the dissociation of SiC, that might be necessary for good wetting, was retarded by the existence of silicon.

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