The aging characteristics of quenched Mg-1.3 wt%Ce alloy were studied by electron microscopy and hardness measurements. On isothermal aging at 150°C, precipitates occurred first on the grain boundaries and dislocations, followed by precipitation within grains. At an early stage of aging at temperatures higher than 200°C, precipitation on the grain boundaries and dislocations, and within grains took place simultaneously. The diffraction effect observed in the present experiment suggests that the precipitates formed and dispersed uniformly within the matrix at an early stage of aging were to be of an intermediate phase in which cerium atoms might be enriched on (10\bar10) planes of the matrix. In a later stage of aging, the precipitates transformed into the equilibrium hexagonal phase of β, ribbon shaped, with the following orientation relationship with the matrix:
(0001)_M⟨11\bar20⟩_M⁄⁄(0001)_P⟨10\bar10⟩_P, c_M≈c_P, 3d_{11\bar20}M\lesssimd_{10\bar10}P.
The ribbon shaped precipitates grew predominantly in the direction of ⟨0001⟩, and, to a much lesser extent, in the direction of ⟨11\bar20⟩ of the matrix. Significant age hardening observed in the present alloy should be associated with the precipitation of fine particles dispersed uniformly in the matrix. A certain amount of the intermediate precipitates appeared to remain even in a stage where the maximum hardness was attained. An activation energy for the age hardening process was determined to be 30 kcal/mol.

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Various methods are used to study the dislocation dynamics in sintered and electron beam melted polycrystalline molybdenum at 300°K . These are double strain rate cycling, incremental unloading and stress relaxation. Special attention is paid to check the mutual consistency of the analytical methods for stress relaxation to obtain the deformation parameters. All methods yield similar values of 6.5±0.5 for the dislocation velocity-stress exponent in both sintered and melted molybdenum. The thermal component of the flow stress, evaluated from stress relaxation, double strain rate cycling and incremental unloading tests, is independent of plastic strain, indicating that work hardening is mainly due to the increase in athermal stress. With a knowledge of the dislocation velocity-stress exponent, m^*, it is deduced from m^*=H_k⁄4kT that the kink energy is 0.67 eV, which is in agreement with those reported for high purity single crystals of molybdenum in the literature.

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The surface tensions of PbCl₂–ZnCl₂ binary melts have been measured by the maximum bubble pressure method in the temperature range up to 200°C above the liquidus. At each composition the surface tension shows a nearly linear decrement with rising temperature. From the values of surface tension and its temperature coefficient, the surface entropy and the surface enthalpy per unit area are determined for the binary melts. These quantities and the surface tension vary only slightly with increasing content of PbCl₂ up to 50 mol% PbCl₂, but increase conspicuously in the PbCl₂-rich side of the system as the content of PbCl₂ increases. The changes in liquid structure or the constituent ionic species have also been estimated on the basis of the results obtained in this experiment and the previously reported data on the density, electric conductivity and viscosity coefficient, etc.

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The Raman spectra of a molten NaNO₃–AgNO₃ mixture are investigated. The variations in frequencies of ν₁, 2ν₂, ν₃ and ν₄ with the concentration of silver nitrate were shown and the splittings of ν₃ and ν₄ were also observed at the region rich in silver nitrate.
Assuming the splitting to be due to the effect of cation field around NO₃⁻, the effect of cation field was estimated by using the Urey-Bradley force field method. It was found that the cation field in the region rich in silver nitrate produced a large effect on the force constants of nitrate ion and such a cation field gradually decreased with decreasing concentration of silver nitrate.
Although it is assumed that the free rotation of nitrate ion about its threefold axis is restricted microscopically in the region rich in silver nitrate as indicated by Wilmshurst, the hinderance of free rotation of NO₃⁻ about its threefold axis does not seem to give any effect on the transport parameters for the NaNO₃–AgNO₃ system.

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The thermoelastic nature and crystal structure of the Cu-∼40 wt%Zn martensite (β₁″), which is formed at temperatures below about −70°C exhibiting a parallelogram shape and may directly be related to the remarkable shape memory effect of the alloy, have been examined by means of low temperature optical and electron microscopy observations and electron and X-ray diffractions. The reverse transformation of β₁″ martensite to β₁ matrix is completed upon heating up to room temperature with a small hysteresis, that is, the martensite is thermoelastic in agreement with a previous observation, although it abruptly appears and disappears upon cooling and heating, respectively. The thermoelastic nature may closely be related to the shape memory effect of the Cu–Zn alloy as well as other marmem alloys.
The crystal structure of the β₁″ martensite is identified as a monoclinic lattice slightly modified from the normal 9R type orthorhombic one (β₁′) observed at room temperature, and lattice parameters of the modified 9R structure are determined to be a=4.412, b=2.678, c=19.19Å, and β=88.43°. The appearance of the modified 9R type β₁″ martensite is attributed to the general tendency that more close packed structures are realized at lower temperature, since composite atoms of the β₁″ martensite are more closely packed than those of the normal 9R type β₁′ martensite. Internal defects of the β₁″ martensite are not twin faults as observed in martensites of other marmem alloys, but stacking faults on the (001) basal plane.

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The static structure factors of liquid gallium and rubidium were measured at several temperatures above their melting points using the time of flight neutron diffractometer installed on the 300 MeV Tohoku University electron linac as a pulsed neutron source. The characteristic oscillation of the structure factor of liquid gallium in a high momentum transfer region has been shown to be well understood in terms of a diatomic molecule-like atomic association with the bond length of 2.69Å. It has been discussed, however, that the subsidiary maximum on the high momentum transfer side of the first peak in the structure factor of liquid gallium may appear due to the second and subsequent peaks in the pair correlation function to shift to a larger distance in comparison with those of simple liquid metals such as alkali metals.

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