The anomalous X-ray scattering (AXS) measurement at the Cu–K absorption edge has been made using synchrotron radiation for characterizing the atomic scale structure of a YBa₂Cu₃O_7−x superconductor. The measured energy dependence arising from the anomalous dispersion effect of copper was quite consistent with the changes expected from the crystallographic structure factor based on a model of the orthorhombic crystal structure in which an oxygen atom at 1b and 1e sites is partially deficient. This result has also been confirmed by the local environmental structure around copper calculated from the present AXS measurement.

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Multilayered Mo/Ge thin films have been prepared by dual rf-sputtering technique, and the interdiffusion and structural change on annealing have been investigated by X-ray diffraction measurements. X-ray diffractometry shows that for the modulation wavelength λ shorter than 5 nm both Mo and Ge sublayers are amorphous, while for λ longer than 5 nm, crystalline bcc structure appears in Mo sublayers. The interdiffusivities have been determined from the decay rate of satellite peak intensity around (000). The temperature dependence of the effective interdiffusivities in amorphous Mo/Ge multilayer films with λ=3.4–4.2 nm is expressed as
\ ildeD_λ=1.3×10⁻¹⁶exp[−(115±7)kJ mol⁻¹⁄RT]m²s⁻¹
over the temperature range from 665 to 724 K. On initial annealing, the satellite peak intensity decreases drastically and the modulation wavelength decreases by 1–2%, which are interpreted to be due to structural relaxation and interdiffusion. The thermodynamic behaviour of the amorphous Mo–Ge system is discussed on the basis of the dependence of the effective interdiffusivity on λ.

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With special attention to the fine structure of electrodeposits and the deposit/substrate interface, the heteroepitaxial growth of nickel electrodeposits on a polycrystalline iron substrate has been studied mainly by transmission electron microscopy. The nickel deposits grow heteroepitaxially even at such a high current density as 500 A/m² on a chemically cleaned substrate iron. The crystallographic orientation relationship between the nickel deposits and the iron substrate is that of Kurdjumov-Sachs, i.e. (110)_α⁄⁄(111)_Ni, [1\bar11]_α⁄⁄[1\bar10]_Ni. The nickel heteroepitaxial deposits consist of columnar crystals which contain dense dislocations at the interface. There dislocations are introduced in order to reduce the misfit strain at the interface.

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In order to measure the Kirkendall marker shift in a precise manner a new technique has been proposed. By the technique one can measure the marker shift as a distance between the Kirkendall marker position after annealing and the edge of the inert foil embedded in a diffusion couple parallel to the diffusion direction as it acts as an indicator for the initial marker position. Since the Kirkendall markers and the edge of the inert foil can bee seen in a sight of a microscope, the measurement is very easy and the accuracy of the data on the marker shifts is expected to be improved. The marker shifts in Cu–Sn alloys have been determined experimentally by this technique.

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The process of the deformation structure development was investigated for Ni and Au irradiated to various fluence levels with D-T neutrons. In Ni irradiated to fluences ranging from 1 to 10×10²¹ n/m², and in Au from 0.5 to 5×10²¹ n/m², the transition in the deformation process from dislocation channeling to deformation by cell formation was observed with increase in the amount of deformation. In the specimens for fluences lower than the minimum fluence of these ranges, the deformation by cell formation was observed to continue until the specimen broke, while the deformation by dislocation channeling for fluences higher than the maximum fluence. The diagram for the deformation structure transition can be illustrated as a function of irradiation fluence and deformation amount.
The difference in the deformation structures of neutron irradiated Au and Ni can be interpreted in terms of the difference in the stacking fault energy. The shape of the stress-strain curves and material ductility were also discussed correlating to the deformation structures.

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The heat contents of the Cu–RE (RE=Y, La, Ce, Pr, Nd) binary alloys were measured in a temperature range of 850 to 1300 K by using a drop calorimeter. The melting temperatures and heats of fusion of the intermetallic compounds (CuRE, Cu₂RE, Cu₄RE and Cu₆RE), the temperatures of other phase changes and the average specific heats of the liquid phases of these alloy systems were derived from the heat content data. The specific heats of the liquid phases show large, positive deviation from the Kopp-Neumann additivity-rule. The entropies of fusion of the ordered compounds were found smaller than those calculated by assuming the liquid alloys to be ideal solutions. This was considered as evidence of the existence of chemical short range order in the liquid alloys. The free energies of mixing of the liquid phases were estimated on the basis of a subregular solution model and the experimental data.

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The fundamental parameter (FP) method for the analysis of seven alloying elements (Al, V, Cr, Fe, Zr, Mo and Sn) in titanium alloys was investigated. The program used for calculation was the XRF-11. One homogeneous titanium alloy was prepared as a reference standard for multi-elements analysis by the plasma electron-beam melting method using several pressed compactions which were prepared from various metal powders and sponge titanium. The chemical composition of it was determined by the JIS and TIS analytical methods. The X-ray fluorescent spectral line overlaps were examined. The net count rate of the pure titanium at the VKα peak angle and that at the TiKα peak angle were measured and then the ratio (m_V.Ti) between them was found to be 0.0064. The net count rate of the Ti–V binary alloys containing no chromium at the CrKα peak angle and that at the VKα peak angle were measured. The ratio (m_Cr.V) between them was 0.0101. For the determination of chromium the count rate for VKα must first be corrected for the interference by TiKβ and then CrKα count rate is corrected for the interference by VKβ. The relative standard deviations of repetitive six measurements for the analytical values of the seven analytes were in the range of 0.30∼1.43%. The determined values for NBS SRMs and IMI CRMs titanium alloys by the FP method agreed well with those certified values.

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In order to clarify the cooling capacity of the two-stage quenching technique by a combination of high-pressure argon gas atomization and centrifugal spinning, the morphology and structure of Fe_85.6C_14.4 and Fe_82.6C_17.4 powedrs produced by the technique were examined as a function of particle size fraction. The powder particle morphology is mainly spherical for small particles below 25 μm in diameter and flaky (with a thickness of about 1 to 4 μm) for particles with sizes above about 44 μm. The as-quenched structure consists of α′+Fe₃C+γ phases for the spherical powders and an amorphous phase for the flaky powders. The formation of the amorphous phase is different from the result of the melt-spun ribbons in which α′+Fe₃C+γ phases are formed. It is therefore concluded that the two-stage quenching technique leading to the formation of flaky powders has an enhanced cooling rate because of a reduced thickness and a large contact surface of the flaky powders obtained by the spinning of super-cooled liquid droplets formed during gas atomization.

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The structure and growth morphology of Al₆₅Cu₁₅Fe_20−xCo_x and Al₆₅Cu₂₀Fe_15−xCo_x alloys have been examined in rapidly solidified, conventionally solidified and fully annealed states. A conventionally solidified Al₆₅Cu₁₅Co₂₀ alloy, which was prepared by the whole substitution of Fe by Co for a stable icosahedral Al₆₅Cu₂₀Fe₁₅ quasicrystal, was found to consist of a stable decagonal quasicrystal with a columnar morphology. The length of the decagonal column is as large as about 0.15 mm and the growth is thought to take place along a preferential direction parallel to the tenfold periodic axis because the plane perpendicular to the longitudinal direction of the column has the morphology of five dendrite arms radiating from the dendrite centers. The finding of the stable decagonal quasicrystal is important in the clarification of the formation mechanism and fundamental properties of the quasicrystals with an icosahedral or a decagonal structure.

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